some work
add snapshotting
Update docs
Make tests pass
refactor in progress
WIP
fix some stuff
update tests, fix more bugs
remove the extra gitignore line from who knows where
Don't emit empty "_chisel_temps_" VCD module

Jim Lawson suggested this fix, but for some reason I seem to have
dropped the ball and not actually committed it...
use the mem_peek command instead of wire_peek for Mem peeks
remove counter_shadow & pseudoMuxes
make only unconsumed top level outputs outs
merge
Avoid redundantly obtaining stack traces

They impose a surprisingly significant runtime penalty.
Remove vestigial reserved keyword support
Remove vestigial saveWidthWarnings variable

We should deprecate --Wwidth, since it does nothing.
Remove vestigial options
Make isEmittingComponents a property of the backend
replace ioMap/ioCount with simpler mechanism