Parsing for quasiquotes
Elaborate quasiquotes
Elaborate qquotes in fresh proof state
Initial support for unquotes
Support simple quasiquote patterns
Allow reflecting types with quasiquote patterns
Quasiquotes in CHANGELOG
Add simple test for quasiquotations
Merge remote-tracking branch 'upstream/master' into quasiquote

Conflicts:
	CHANGELOG
Implement unquoting for the rest of PTerm
Elaborate quasiquote patterns to something useful

This causes parts of the terms that either vary unpredictably or don't
contain interesting information to be elaborated to _ in a pattern-match
context.
Update comments to fit the state of the code
Fix type error in generated quasiquote patterns
Merge remote-tracking branch 'refs/remotes/upstream/master' into quasiquote

Conflicts:
	CHANGELOG
Merge pull request #1331 from david-christiansen/quasiquote

Quasiquote support