Purge entries from swapped candidates map once the picking algorithm moves its current index past them.
Ignore worksheet directory.
Extra examples in worksheet to show semantics of 'withDefault' in immutable and mutable maps.
Add extra test to analyse precisely how 'testPig12' is failing with an OOM - this test is essentially a copy of the failing test, except that it succeeds by virtue of not selecting *all* of the items from the input sequence.
Winner! Fixed OOM bug observed when running 'testPig12'.
Merge in bugfix for OOM observed in 'testPig12'.
Merge duplicated changesets caused by syncing with Git from OSX.