Improve readme a bit

Climax777 · Climax777 · commit 28ced250d151 · 2014-12-04T14:48:57.000+02:00
diff --git a/README.md b/README.md
@@ -1,4 +1,8 @@
 mongo-cxx-pool
 ==============
 
-A simple connection pool for mongo's C++ client driver
+A simple connection pool for mongo's C++ client driver. This is strongly based on the old ScopedDBConnection pool the driver used to provide.
+
+This pool can handle authentication also. Please note that `authSource` and `authMechanism` must be specified.
+
+This library requires a C++-11 compatible compiler.
