Add labeled fences to most code blocks, monospace terms where
appropriate, omit "$" when referring to variables

Also changes some heading levels so only one primary
heading appears per page.

Fixes to spelling and punctuation for consistency and readability.

GitHub now nicely generates a documentation site for us at
http://brew.sh/brew based on our docs folder. Optimise the output of
this and the GitHub docs directory for readability and the various user
groupings.

Mostly related to the newer ways we’re handling versions and the
incoming deprecation of devel-only, head-only and versions.

By the commit edf000e4, bash and zsh
completion scripts have been moved to `etc/bash_completion.d/brew` and
`share/zsh/site-functions/_brew`, respectively. Now completion will be
done automatically without any trick.

From `Library/Contributions/brew_zsh_completion.zsh`:

````bash
````

Then it should give symlinked file name of `_brew` instead of being just `brew_zsh_completion.zsh`

Closes Homebrew/homebrew#48897.

Signed-off-by: Dominyk Tiller <dominyktiller@gmail.com>

Remove duplication, link to the API documentation more often,
tweak wording, add `@UniqMartin` as a maintainer, note `@jacknagel`'s
and `@adamv`'s significant past contributions to Homebrew, delete some
outdated or unneeded documentation, add some missing `Formula` API.
entries and simplify/improve `CONTRIBUTING.md`.

Closes Homebrew/homebrew#46179.

Closes Homebrew/homebrew#46618.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>

Closes Homebrew/homebrew#46408.

Signed-off-by: Alex Dunn <dunn.alex@gmail.com>

I find brew switch very helpful to activate a different version of an
installed formula. This seems worth calling out in the documentation to
elevate awareness.

Closes Homebrew/homebrew#45694.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>

Always use the `<user/repo>` format as used by the `brew tap` command.
Also fixed a link to `homebrew/head-only` and sorted a list in `FAQ.md`
in alphabetical order.

Closes Homebrew/homebrew#45535.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>

Closes Homebrew/homebrew#43363.

Signed-off-by: Alex Dunn <dunn.alex@gmail.com>

changed from `brew --repository` to $(brew --repository)

Closes Homebrew/homebrew#38352.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>

A simple vim plugin created by me. Hope it can help formula authors who use vim.

Closes Homebrew/homebrew#38150.

Signed-off-by: Xu Cheng <xucheng@me.com>

Reference.
* GitHub: https://github.com/about
* Xcode: https://developer.apple.com/xcode
* Zsh: http://www.zsh.org



Closes Homebrew/homebrew#37866.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>

Closes Homebrew/homebrew#33211.