Fix bug causing instantiation to exclude immediate container

Change-Id: Ia669ca6e7d0b34e7f8e2de551275a64e02bb060c
Store list of containers in tuples (for debugging)

Change-Id: I238404bd352b404ec5f348fbe98ee42870cf7989
Show container information for debugging

Change-Id: If3fd0f6f1dbe45e8da945ae08d0bf68dfadbd1be
Change language from modified to amended

Because the original tuple is never modified

Change-Id: Icde2100ae950bc4e70a3b2ae8c53c10259646049
State that XQuery uses trees, not tables.

Change-Id: If35edae8ee6bc8a64cd37c57b9970c02629f9c1e
Update null example

Change-Id: If85a805addfc8d5146a3638a6ea53bcf59bfb6d6
Remove “modified” from spec

Change-Id: Id461716a768fcfc75b65dd0b921cda457f52ed33