Add a test to prevent Mash from losing indifferent_access of nested hash

See discussion at https://github.com/intridea/hashie/pull/197
Merge pull request #219 from kenips/bug/add_test_case_for_197

Add a test to prevent Mash from losing indifferent_access of nested hash
Add spec from #112 for Trash subclasses
Merge pull request #220 from michaelherold/add-spec-for-trash-subclassing

Add spec from #112 for Trash subclasses
suffix parser pattern is constant - we shouldn't compile it every time for suffix recognition
Merge pull request #221 from kubum/object-alloc

Object allocation during parsing method name