GitLab

- Add mercurial support to af-magic, so now the vcs prompt will show up in either a git or hg repository
- The virtualenv prompt was white and bumped up against the user@hostname output
- Fixed that so its green (which I thought highlighted it more thematically) and has a space before user@hostname

Fixes #7942

Provisional measure due to "Unexpected value 'if'" error. See https://github.community/t5/GitHub-API-Development-and/jobs-lt-job-id-gt-if-not-working/m-p/28980

This allows you to use `colored git log --help` for example, to get
colored output.

This reverts commit 59c1ec80.

Fixes #7985

Removing plugin that was named after an external tool, which carries a history as a racist phrase. Was reported by a user of OMZ who shared some background on the terminology and how it made them feel. (#8027)

The original suggestion for an unattended install downloads the installation script to a file, then runs that file with the --unattended argument. The install.sh file would be left behind after the suggested command was run.
This change passes the --unattended argument directly into sh. So, it's a nice one-liner like the default installation script, and it doesn't leave a dangling install.sh script.

After wandering into a few articles that discuss the difference between might and may...opting for may.

Redirect stderr to avoid printing errors to the console when the ssh key is not
unlocked.

Add better usage instructions for the plugin which actually work

Just add aliases for PVC actions.

* git: add `alias grev="git revert"`

* Swapping double for single quotes

Matching the conventions in the plugin

* Clean up plugin and README
* Rename ag to age to avoid conflict with The Silver Searcher
  Fixes #3866

* Use double quotes to cache value of $apt_pref and $apt_upgr
* Clean up and fix syntax of command checks
* Clean up README and document $apt_pref/$apt_upgr overriding mechanism
* Rename `ag` alias (apt upgrade) to `au`
* Clean up README and fix syntax

Fixes #3686 
Fixes #4660 
Closes #5906
Co-authored-by: Noah Vesely <fowlslegs@riseup.net>