more examples in fixtures
#persisted?
be more specific on error
Merge branch 'master' into relations_part1

Conflicts:
	lib/locomotive/adapters/memory_adapter.rb
	spec/unit/adapters/memory/dataset_spec.rb
	spec/unit/adapters/memory_adapter_spec.rb
n-1 relationship attempt
lazy loading association
Merge branch 'master' into relations_part1

Conflicts:
	lib/locomotive/mapper.rb
	lib/locomotive/mapping.rb
	lib/locomotive/mapping/coercer.rb
	spec/fixtures/example_mapper.rb
Merge branch 'master' into relations_part1

Conflicts:
	spec/support/adapters/memory.rb
remove drafts and unrelated files
Merge pull request #18 from locomotivecms/relationships_part1

Relationships part1