SI-8350 treat single parens equivalently to no-parens in new

q"new C" and q"new C()" have identical trees after parsing. This
commit adds knowledge of this invariant to SyntacticNew.
SI-8387 don't match new as a function application
SI-8451 quasiquotes now handle quirks of secondary constructors

Apparently even though the rhs of a secondary constructor looks like an expr,
it always gets wrapped in a block by the parser. This works just fine with
the typer, but crashes in uncurry. This commit brings quasiquotes in line with the parser.
Merge pull request #3659 from xeno-by/topic/uncurry-ctors

SI-8451 makes uncurry more forgiving
Merge pull request #3656 from densh/si/8387-8350

SI-8350 SI-8387 tweak handling of new trees