changed variable reference assignment to support php 5.6
added php 5.5 and 5.6 as versions to test with
removed all items under allow_failures and added php5.5 and 5.6 versions to exclusion/inclusion
removed everything that wasn't phantomjs or default from test matrix
Merge pull request #731 from thecoolestguy/730_var_by_ref_bugfix

changed variable reference assignment to support php 5.6