Define ImportTop to cause BsimTop, PcieTop, and ZynqTop to import a user-defined package

Change-Id: I89114e6e873767c04b069f5ced60e751146d7269
In your Makefile, define PIN_TYPE to have bsc define PinType

Change-Id: I0456c7ee867596ecb59b7974256cdaceb28b7e2a
added zc706 and zedboard switches to boardinfo

Change-Id: Id1b33575d7722c91f7d601d7a69b44306926e85a