Generalize type info parsing.

To enable parsing of getelem / setelem messages.
Implement parsing for getelem / setelem.

Rest of the coach still assumes getprop / setprop, though.
Add assertions to catch stray element reports.

Currently, these reports are not handled separately, so these assertions
will trigger.
Clarify handling of singletons.
Refactor report hierarchy to allow for element reports.
notes
Move property report-specific analysis to a separate file.

That's pretty much all the analysis so far.

The techniques that do apply to other kinds of reports (e.g. locality
merging, temporal merging) are currently mixed with the rest of the
analysis code. Try factoring it out to reuse some of it.
Note on irrelevant failure pruning.
Add missing contract.
Fix corner case.
Don't print property for non-property locations.
Ingore more files.
First stab at element reports.
Note on SplayLatency.
Add NavierStokes benchmark.

Has two element reports, but in lukewarm code (~5%).