Rubocop offense fixes

In various templates, fix:

 - C: Use 2 spaces for indentation in an array, relative to the start of the line where the left bracket is.
 - C: Extra empty line detected at block body beginning.
 - C: %-literals should be delimited by ( and )
 - C: C: Use %r only for regular expressions matching more than 1 '/' character.
 - C: Extra empty line detected at block body end.