Remove prominent license boilerplates from files

By now all the files were completely rewritten, so I don't think it's
necessary to keep all the irritating license notices. The authors of the
Xitip program are now mentioned in LICENSE.rst and I will add a few
comments in the README.

LICENSE.rst

@@ -0,0 +1,35 @@
+Citip -- Information Theoretic Inequality Prover (C++/CLI version)
+
+Copyright (C) 2015 Thomas Gläßle <[email protected]>
+                   http://github.com/coldfix/Citip
+
+This program is derived from Xitip (but completely rewritten by now). Xitip
+was created by:
+
+Copyright (C) 2007 Rethnakaran Pulikkoonattu,
+                   Etienne Perron,
+                   Suhas Diggavi.
+                   Information Processing Group,
+                   Ecole Polytechnique Federale de Lausanne,
+                   EPFL, Switzerland, CH-1005
+                   Email: [email protected]
+                          [email protected]
+                          [email protected]
+                   http://ipg.epfl.ch
+                   http://xitip.epfl.ch
+
+The details of the licensing terms of the above mentioned software shall
+be obtained from the respective websites and owners.
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.

Makefile

@@ -1,43 +1,3 @@
-#  Citip -- Information Theoretic Inequality Prover (C++/CLI version)
-#
-#  Copyright (C) 2015 Thomas Gläßle <[email protected]>
-#                     http://github.com/coldfix/Citip
-#
-#  This file is copied from the Xitip program and possibly modified. For a
-#  detailed list of changes from the original file, see the git version
-#  history.
-#
-#  Copyright (C) 2007 Rethnakaran Pulikkoonattu,
-#                     Etienne Perron,
-#                     Suhas Diggavi.
-#                     Information Processing Group,
-#                     Ecole Polytechnique Federale de Lausanne,
-#                     EPFL, Switzerland, CH-1005
-#                     Email: [email protected]
-#                            [email protected]
-#                            [email protected]
-#                     http://ipg.epfl.ch
-#                     http://xitip.epfl.ch
-#  Dependent utilities:
-#  The program uses two other softwares
-#  1) The ITIP software developed by Raymond Yeung
-#  2) The GLPK (GNU Linear Programming Kit) for linear programming
-#  The details of the licensing terms of the above mentioned software shall
-#  be obtained from the respective websites and owners.
-#
-#  This program is free software: you can redistribute it and/or modify
-#  it under the terms of the GNU General Public License as published by
-#  the Free Software Foundation, either version 3 of the License, or
-#  (at your option) any later version.
-#
-#  This program is distributed in the hope that it will be useful,
-#  but WITHOUT ANY WARRANTY; without even the implied warranty of
-#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-#  GNU General Public License for more details.
-#
-#  You should have received a copy of the GNU General Public License
-#  along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
 CC=gcc
 CFLAGS=
 LDFLAGS=

main.cpp

@@ -1,43 +1,4 @@
-/*
-    Citip -- Information Theoretic Inequality Prover (C++/CLI version)
-
-    Copyright (C) 2015 Thomas Gläßle <[email protected]>
-                       http://github.com/coldfix/Citip
-
-    main.cpp is the main C++ program file of the ITIP CLI frontend.
-    The file is based on the Xitip.c from the Xitip program:
-
-    Copyright (C) 2007 Rethnakaran Pulikkoonattu,
-                       Etienne Perron,
-                       Suhas Diggavi.
-                       Information Processing Group,
-                       Ecole Polytechnique Federale de Lausanne,
-                       EPFL, Switzerland, CH-1005
-                       Email: [email protected]
-                              [email protected]
-                              [email protected]
-                       http://ipg.epfl.ch
-                       http://xitip.epfl.ch
-    Dependent utilities:
-    The program uses two other softwares
-    1) The ITIP software developed by Raymond Yeung
-    2) The GLPK (GNU Linear Programming Kit) for linear programming
-    The details of the licensing terms of the above mentioned software shall
-    be obtained from the respective websites and owners.
-
-    This program is free software: you can redistribute it and/or modify
-    it under the terms of the GNU General Public License as published by
-    the Free Software Foundation, either version 3 of the License, or
-    (at your option) any later version.
-
-    This program is distributed in the hope that it will be useful,
-    but WITHOUT ANY WARRANTY; without even the implied warranty of
-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    GNU General Public License for more details.
-
-    You should have received a copy of the GNU General Public License
-    along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
+// This is the main C++ program file of the ITIP CLI frontend.
 
 #include <iostream>     // cin/cerr etc ...
 #include <string>       // getline