Merge pull request #89 from xplanes/master

Added NMake and VS2012 compiler options
Update readme.txt
Merge pull request #90 from xplanes/master

ENH: Added CMake project compiler specific settings
Updated version from 2.5.1-beta to 2.5.1.
Updated doc config and fix doc error.
Added vs11 search in the registry. Relates to #91.
Updated python version in doc.
Updated installer configuration.
Pause before deleting files to avoid locks.
Increase range of cmake versions.
Merge pull request #92 from xplanes/master

FIX: Ignore .svn folder when comparing repositories
ENH: Force to use version 2.8 of wxWidgets
Converted and updated readme file.