[Truffle] Fix Kernel#p for nil.
[Truffle] Add Debug#parse_tree.
Add an indenting version of Node.toString.
[Truffle] Use indentation for Debug#parse_tree.
[Truffle] Fix lots of block specs.
[Truffle] Add profiles to destructure switch.
Visit ArgumentNode.
[Truffle] Use a visitor to find parameter names.
[Truffle] Fix caller frames.
Make AbstractNodeVisitor more abstract.
Parameterise NodeVisitor.
[Truffle] Pull out some common translator stuff, and make sequence node flatten.
[Truffle] The destructure switch doesn't need to have the body as a child.
[Truffle] Ask JRuby for arity instead of working it out ourselves.
[Truffle] Basics of new argument load translator working.
[Truffle] New argument load translator handling simple rests.
[Truffle] New argument loader working with post arguments.
[Truffle] Use full tree to compare new argument load against previous.
[Truffle] Speculatively turn on new argument load.
[Truffle] Count failed argument translations.