Uninstall should delete the endpoints field to allow removal of the field_endpoints module. Fixes #1303016

Moved the whole Views options thing to the right class, dereine patched Views for us and I made sure the query, no matter how complicated is well indexed.

Partial rollback of commit by naught101: change name back to label, except on relation_type editing form.

Issue #1165286 by naught101: Changed Label->Name everywhere, fixes machine_name. Also fix some coding inconsistencies.

Issue #1152024 by naught101: Fixed When updating a relation type, it tries to recreates the field instance instead of update it.

relation->entity_keys is now relation->endpoints[LANGUAGE_NONE]. Free MongoDB support. Less custom code. Bliss.

Issue #1113654: naught101 - implement relation_save, use it for relation_create, and fix a few erros from previous commits. Tests don't pass.

settings for ary>2 / ary = 2, arity validaton, predicate edit works on nonexisting predicates, bundles are non required on config

#981364 by sun, naught, chx: fix field schema column and variable names. fix hook_field_is_empty() implementation.