Update makefile compiler detection

- Fixed minor mistake with makefile compiler detection

MPI_calculatePairVectorAvg Update (#68)

- Resolves #66
- Updated .gitignore file to ignore the packages directory created by Visual Studio
- Updated Doxyfile to new version v2.1.0-beta.1
- Added new MPI_calculatePairVectorAvg function to Utils
- Updated calculateProbHistAvg to throw exception on all processors if the input histogram on any proc is too small or if bin sizes do not match
- Updated Version class with the new version string v2.1.0-beta.1
- Updated test_mpi.cpp by adding CalculatePairVectorAvgTests with new unit tests for the Utils::MPI_calculatePairVectorAvg function
- Updated test_mpi.cpp CalculateProbHistAvgTests by adding tests to check for the output histogram range and to check exception throwing when input histograms are too small or have different bin sizes
- Updated Doxygen documentation
- Updated Changelog to note the changes in this commit

Fix joss paper (#64)

* JOSS Paper Fix
-Corrected typo in paper.md
-Updated README latest stable version info to v2.0.1
-Updated version_string in Version.cpp to v2.0.1
-Updated Doxygen documentation files for v2.0.1
-Updated CHANGELOG to note all changes in v2.0.1

Joss edits (#63)

Resolves #59 and #62 
-Updated CHANGELOG with notes about the most recent changes
-Made several previous changelog notes more concise
-Corrected errors in the paper bibtex entry formatting and added some missing reference info 
-Fixed incorrect copyright statement years in test.cpp and test_mpi.cpp
-Added line to .gitignore file to ignore the x64 build directory
-Added default values for all parameters in Parameters_Simulation and Parameters_Lattice to avoid undefined behavior with uninitialized parameters
-Added tests that the default values for the Parameters_Simulation and Parameters_Lattice objects are invalid parameters
-Fixed several typos and spelling mistakes in the documentation source files
-Updated the Doxygen documentation files
-Updated changelog heading for the changes coming in v2.0.0
-Updated README by changing current status to note the release of a stable v2.0
-Updated README by modifying the acknowledgements for v2.0

Spelling Fixes (#56)

[skip ci]

Update Changelog Release Date (#54)

[skip ci]

Fixed Recalculation Cutoff Problem (#43)

-Resolves #42

Simulation class:
-added new member variable Recalc_cutoff_sq_lat to be used by the findRecalcNeighbors function instead of const static local variable so that its value can be updated when calling the init function

Merge pull request #17 from MikeHeiber/development

Next beta release candidate

Merge pull request #12 from MikeHeiber/development

v2.0-beta.3 Development

Merge pull request #11 from MikeHeiber/development

Development v2.0-beta.2 Candidate2