Add ConsecutiveSilentScripts linter

Add linter which checks for multiple lines of Ruby script that can be
condensed into a `:ruby` filter block.

Change-Id: I6cee9e930dda71a3f65005f9bbbae25a85161015
Reviewed-on: http://gerrit.causes.com/42359
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane.dasilva@brigade.com>