Updates changed method names and fixes spec failures

This allows the BetterErrors REPL to be available
when your GitLab instance is listening on
something _other_ than localhost.

[ci skip]

quiet_assets has been seemingly abandoned, and now sprockets-rails has the feature built-in!

From this PR: https://github.com/rails/sprockets-rails/pull/355

This reverts commit 3e991230.

# Conflicts:
#	app/models/project.rb

Sent emails in the development environment will no longer automatically
be opened in the browser. If a sent email needs to be viewed, it can be
found at the `/rails/letter_opener` route.

Fix underscore template error.
Fix `=` spacing

This allows you to do:

    rake dev:setup BOOTSTRAP=1

and prevent dozens of letter_opener emai popups in your browser.

This can be used to measure the time (roughly) spent on a per line
basis. This can also be used to measure timings for views, for example
by adding the following to a URL:

   ?lineprof=app/views/projects/notes/_note

rack-lineprof is only enabled when:

1. The application runs in development mode
2. The used Ruby is MRI
3. The environment variable ENABLE_LINEPROF is set to a non-empty value

It's good for debugging javacsript, but creates massive amounts of http request
by adding each javascript individually. Only turn it on while debugging js code.

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>