Implement a Table collection type.

[jmalloc]

Concept:

• Table provides an memory efficient way to store tabular data.
• Table is a MutableRandomAccessInterface with elements that are MutableAssociativeInterface.
• Table has immutable key names that form the keys of the Table's associative elements.

Implementation:

• Flattened Vector of values ordered to match the Table's key names.
• Iteration should produce a TableElement that references the inlined Vector elements.
• Inserting or removing an element from a Table may invalidate TableElements referencing later elements.

FYI @ezzatron

[jmalloc]

FYI @ezzatron I've moved this into the feature/table branch.