Add support for serializing all model and class fields

Add a new property the schema.json can specify for a table model
or class which will serialize all field names, even if a field
definition does not include a serialized_name value.
Remove unnecessary check when adding SerializedName import

The if statement that determines if the import for SerializedName
doesn't need to include checks on both serializeAllNames and
hasSerializedNames, since hasSerializedNames checks if all names
are serialized.
Merge pull request #8 from BrightcoveConsultingReusableComponents/serialize-all-names

Add support for serializing all model and class fields