scripts: Add repository url parser

This simplies the install process so one can install modules by typing:
bin/zmm install <REPO_URL>. The repo parser also opens the way for
future module namespacing, so we can install modules as
arjan/mod_asterisk. More work needs to be done to parse more URLs.

Other fixes:
* Remove -p/--path option since -s/--site option can be used site-specific actions
* Add restart and reinstall subcommands
* Improve ZMM usage text