[Cmake] FindPerl.cmake, FindHhc.cmake

[Sebastien BARRE]

Hi

Just for info, I added two small modules:

  - FindPerl.cmake : find Perl (also looks in "C:/Perl/bin" and in the 
registry to find ActiveState Perl)

  - FindHhc.cmake : find Microsoft HTML Help Compiler ("C:/Program 
Files/HTML Help Workshop"  + registry)

Seb