Merge pull request #4 from devin-c/master

postpone scope verification until it's used
Ignoring the RVMRC.
Merge remote-tracking branch 'origin/master'
Bumping version to 1.2.5.
use attribute_names instead of deep copy attributes to filter attributes
bump to 1.2.6
Allow excluding serializable fields at the class level.
Removing the protoable_attribute method in favor of useing field_from_record.
Renaming #protoable_attributes to #fields_from_record for parity with #attributes_from_proto.
Removing the #to_proto_hash method because it's an unnecessarry abstraction.
Removing extra references to the custom attribute converters.
Removing the field converters in favor of attribute from proto.
Added a new transformation module to consolidate all proto => record transformations.
Renaming the fields module to columns.
Moving transformation specs to their own file.
Consolidating column methods into the columns module.
No more converters.
Consolidating column specs.
Consolidating serialization conversions.
Consolidating transformation conversions.