Remove -x alias for --xml argument

Change-Id: Iaa52cddf0681ca7b8788b013f5cfa9b6ebc9ce5c
Reviewed-on: https://gerrit.causes.com/27801
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>
Change -i --ignore-linter to -x --exclude-linter

Change-Id: I4f1174d2b0a13d6f68d1e70a610287e97ee6335e
Reviewed-on: https://gerrit.causes.com/27802
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>
Add -i --include-linters option

Change-Id: I10e274276e56e60052c6471a5b21c00576fd40a0
Reviewed-on: https://gerrit.causes.com/27803
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>
Remove unnecessary `require 'sass'` lines

This lines are a historical artifact of a time before we used the
Visitor pattern for the `Linter` class. Since `lib/scss_lint.rb`
`require`s the `sass` library in order to monkey patch its parse tree,
we don't need to duplicate those require statements.

Change-Id: I8c3a569b4ef7ca40e365a234b341312e7f5c3687
Reviewed-on: https://gerrit.causes.com/27806
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>
Remove unnecessary `require 'scss_lint'` lines

These lines were unnecessary since the `scss_lint` module has already
been loaded by the time these files are executed.

Change-Id: I708316bf25e560c532295980cd9d77e88a683459
Reviewed-on: https://gerrit.causes.com/27807
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>