Updates gitflow aliases
Adds `gcundo` git alias to undo last commit before a push.
Fixes `alf epoch` so that `arg_file` is set correctly to `default` if no arguments have been passed.
Fixes issue with calculating startup time.
Fixes issue with creating alf version number
Updates `ALF_UPDATE_DAYS` to 30 days
Updates .zshenv to disable alf auto updates.
Bumps to v1.0.15
Merge branch 'release/1.0.15' into develop