Use cljs analyzer API to not pull all metadata to run time

[borkdude]

When writing (meta (var x)) in CLJS, you basically pull all metadata to the runtime. Instead you can do:

(ana/resolve {} 'memfn)

at compile time, then inspect some metadata and only copy what is needed to the runtime.

We can leverage this better in sci.impl.namespaces and sci.core.

[borkdude]

In branch resolve-better this saves about 100kb: 900kb -> 800kb. More space can be saved by moving more stuff to compile time in the expanded code and maybe moving some cond-> stuff into a function.