update requirements for elastic-git
Merge branch 'feature/issue-21-specify-content-license' into feature/issue-26-use-elastic-git
stop compiling libgit2
migrate repo to EG format
move context processor to EG
update models file
Merge branch 'develop' into feature/issue-26-use-elastic-git
work in progress
Merge branch 'develop' into feature/issue-26-use-elastic-git

Conflicts:
	cms/context_processors.py
	cms/models.py
test_create_post passing
more tests passing
test_page_recreated_if_not_in_git
test_category_position_is_saved
more tests working
tests pass with elasticgit
do not import pygit2
launch ES on travis
tests for context-processors
better tests for import_for_git
remove unused base test