[Fix #974] New cop CommentIndentation

Checks that comment lines have the same indentation as the next
non-blank line, except in the special cases when the next line is
end, }, or ], and the comment indentation shall be one step more.
Merge pull request #1039 from jonas054/fix_974_comment_indentation

[Fix #974] New cop CommentIndentation
Add EachWithObject cop

This cop looks for inject / reduce calls where the passed in object is
returned at the end and so could be replace by each_with_object without
the need to return the object at the end.
Merge pull request #1033 from geniou/each_with_object

Add EachWithObject cop
[Fix #1036] Handle strings like __FILE__ in LineEndConcatenation