bugfix: support path separators in module path

As described by http://docs.ansible.com/intro_configuration.html#library the library supports multiple paths to load modules from. 

Currently `setup.py` treats something like `/usr/share/ansible:/my/custom/modules` as a single directory name and results in the installed modules not being on the module path. (instead they are in a directory named `/usr/share/ansible:/my/custom/modules`) 

This commit simply takes the first listed directory as the install directory for the core modules.
Fixes #5679: lineinfile ignores newline in line argument
Fix a bug in "hg" module so that `pull` is not set to a version.

There is a bug in the `hg` module where if a `tag` is used it won't
properly be able to update to it.

This problem is exhibited on repository where a tag is moved from an
older commit to a newer commit.
Merge branch 'patch-1' of https://github.com/eggsby/ansible into eggsby-patch-1
Tweak library installation path to default to /usr/share/ansible if specified
Merge branch 'fix-5679' of https://github.com/jirutka/ansible into jirutka-fix-5679
Merge branch 'devel' of https://github.com/calebbrown/ansible into calebbrown-devel
pip module wasn't adding -e when using VCS
Document use_mirrors as a no-op for pip module
Remove use-mirrors logic