Add allow_extra_spaces option to SpaceAfterPropertyColon

Change-Id: I998f1d22705846c386ecbb2701faeaecacc826d9
Reviewed-on: http://gerrit.causes.com/36948
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>
Fix bug in `SpaceBeforeBrace` linter

When using `{` in single quotes.

Change-Id: Idc1a527ba12a9b014f6b0a3afad55b61c82faa3a
Reviewed-on: http://gerrit.causes.com/36949
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>
Fix source_from_range with lines with no semicolon

The `StringQuotes` linter would fail on `@import` lines with no
semicolon (which is allowed if they are the last line in the file).

This was causes by the fact that the Sass parser will return the end
position line after the actual last line if there is no semicolon.

Fix by returning an empty string if attempting to fetch the contents of
a nonexistent line.

Change-Id: I5a75a22615a3131dc1571bc1768df02d4f3a3912
Reviewed-on: http://gerrit.causes.com/36952
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>
Cut version 0.22.0

Change-Id: I7e757609f2f38b22e4648d439dd902a81c1d496c
Reviewed-on: http://gerrit.causes.com/36950
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>