wip: mrhyde interception of seq 'constructors'

First attempts at intercepting calls to some seq types.
The goal is to patch cljs so that the object is created
as normal, and then custom code runs after the fact to
add additional functionality to the object.
mrhyde: successfully patched PersistentVector initialization

In the most cavalier (foolish?) move yet, I replace
the cljs.core.PersistentVector object with my own
wrapper. Everything works, but this technique not
surprisingly doesn't help other types like LazySeq.
Further thought needed to think about next steps.

For now, committing this patch in hopes that it
is useful for map types, which are next.
mrhyde: patched cljs.core.ObjMap initialization with auto-accessors

In quadtree it is no longer necessary to call (patch-map) on
map literals, they are automatically patched via me intercepting
the cljs.core.ObjMap object and patch-map'ing all newly
constructed instances.