Switch Reek hook to use extract_messages

In the process updated the specs to reflect the fact that all warnings
returned by this tool are treated as errors by default.

Change-Id: I8fffa26289b9164b5028d87f8864ec50f5ca1443
Reviewed-on: http://gerrit.causes.com/44905
Tested-by: jenkins <jenkins@brigade.com>
Reviewed-by: Shane da Silva <shane.dasilva@brigade.com>
Fix RunAll context to define modified_lines_in_file

Change-Id: Ic3553043bff52a5a2893b41813f866e88ca75752
Reviewed-on: http://gerrit.causes.com/44906
Tested-by: jenkins <jenkins@brigade.com>
Reviewed-by: Shane da Silva <shane.dasilva@brigade.com>