Use lowercase for cmake commands consistenly

Use lowercase for cmake commands consistenly

Inspired from https://github.com/InsightSoftwareConsortium/ITK/blob/master/Utilities/Maintenance/HowToCreateTheCMakeCaseConversion.txt
This needs vim 7.3 and fails with vim 7.4

This also fixes a number of :
- missing empty line at end of files
- useless space at end of lines