ExternalProject: Optimize git operations
I optimized ExternalProject_Add's git clone
by removing 'git submodule init', and generate more optimized *-populate-gitclone.cmake
According to git documentation:
...you can also just use git submodule update --init
without the
explicit init
step if you do not intend to customize any submodule locations.
Example of initialization from Blender repository: https://wiki.blender.org/wiki/Tools/Git
Topic-rename: ExternalProject-optimize-git
Edited by Brad King