Mark the given range instead of 1st pos in clang formatter.

Currently, the given range is still just one column for a lot of cops.
Remove Rubocop::Cop::Location and use Parser::Source::Range instead.
Improve the choice of which range is reported in some cops.
Update CHANGELOG regarding change in clang formatter.
Merge pull request #314 from jonas054/extend_details

Extend details
Move the rails cops exclussion into the #run method
Use empty array to collect cop offences

If we have syntax errors the method will return early and the code will
never actually return the syntax errors and the real offences together.
Using the empty array more clearly express the intend.
Merge pull request #313 from edzhelyov/small-cleanup-in-cli

Move the rails cops exclussion into the #run method