adding support for clang compilation in compile.sh
Fix compilation not working correctly with other compilers than gcc.
Fix no default "cc" compiler being used.
Doc updates
Fix using $() instead of ${} for COMPILER variable.
Merge pull request #1 from necrophcodr/develop

Fix compilation not working correctly with other compilers than gcc.
Merge pull request #19 from jmrenouard/master

adding support for clang compilation in compile.sh