Reorganize packages

[donggyukim]

@davidbiancolin @jackkoenig

1. Reorganize package & directory structures as follows:

• midas: midas compiler + configs
  • core: core chisel implementations(daisy chains, simulation wrapper, zynq shim)
  • passes: compiler passes & transforms
  • widgets: all widget implementations(previously midas_widgets)
• strober
  • replay: customized compiler for sample replays

2. Capitalize file names, split files if necessary(e.g. daisy.scala).
3. Clean up dead code revealed by this PR.
4. Put misc(scripts) in resources.

I think it's almost ready to call this repo MIDAS.

[davidbiancolin]

This definitely feels like motion in the right direction. What remains before we can push it to ucb-bar/midas.git

It's not clear to me what you mean by "core: core chisel implementations(daisy chains, simulation wrapper, zynq shim)" At this point, it sort of feel like "everything else".

[donggyukim]

In my opinion, core contains core components of simulation necessary for simulation mapping. ZynqShim probably doesn't fit into this category, then we may move it to widgets.