[NetlistBrowser] Cell Instance Schematic Viewer

[clavin-xlnx]

This PR augments the NetlistBrowser tool with a logical netlist schematic viewer that has a similar flavor to what is found in Vivado. It is built on a combination of RapidWright's logical netlist, Eclipse Layout Kernel (ELK) and Qt Jambi.

Currently, it only displays one hierarchical cell instance at the top level, but you can descend into lower levels of hierarchy by expanding hierarchical cells. Here is an example screenshot:

Users can navigate the netlist on the left netlist tree browser. If a user selects a hierarchical cell, it will render the logical netlist of that cell in the right hand pane. Blue blocks are hierarchical cells (expandable with the + button) and yellow blocks are leaf cells. There is some limited selection capability by selecting cells, ports and nets on the schematic that will highlight in the right hand tree browser the netlist item.

Example to run:

git fetch
git checkout schematic
./gradlew compileJava
git submodule update --init #If this hasn't been done already before
rapidwright NetlistBrowser test/RapidWrightDCP/microblazeAndILA_3pblocks.dcp

[coherent17]

Can netlistbrowser also support recursive search for a given cell name? It could be hierarchical or either the leaf cell.

This util is really helpful on debugging netlist post Vivado processing.