Document ResolveTargetDocumentListener (fixes #904)
Merge pull request #930 from doctrine/doc-resolve-target-document-listener

Document ResolveTargetDocumentListener
Remove unreachable code in PersistenceBuilder

Many-type associations are skipped earlier in the function, so these blocks are no longer reached.
OC refactoring for PersistentCollection

This removes an assignment of isDirty to true after iterating through "NEW objects"; however, since $newObjects would only be populated if the collection was dirty (per the earlier if condition), the assignment was likely redundant.
Merge pull request #931 from doctrine/pb-cleanup

PersistentCollection and PersistenceBuilder cleanup
Make "target-document" optional for associations (in XSD)
Merge pull request #926
Simple references should require target document
Merge pull request #934 from doctrine/require-target-document

Simple references should require target document
Remove redundant use="optional" attributes in XSD
Merge pull request #935 from doctrine/cleanup-xsd

Remove redundant use="optional" attributes in XSD
Fix remove cascade through uninitialized Proxy objects

Corresponding ORM fix: doctrine/doctrine2@acaf08d4b751f1fc9772de5c0e0c5d8371722f17

See: http://www.doctrine-project.org/jira/browse/DDC-1193
Merge pull request #936

Fix remove cascade through uninitialized Proxy objects
Remove obsolete "callbacks" cascade option

Removes "callbacks" from the $mapping['cascade'] array and the $mapping['isCascadeCallbacks'] boolean.
Merge pull request #903 from doctrine/remove-isCascadeCallbacks

Remove obsolete "callbacks" cascade option
Ensure discriminator field is always set on insert/upsert

Previously, if the discriminator value was not set (e.g. no map defined), the discriminator field would never be set.
Regression test for #942 (discriminator not set on insert/upsert)
Merge pull request #942
Fix typo: duplicate "stored"
Merge pull request #947 from ifdattic/patch-1

Fix typo: duplicate "stored"