Change "RTL" to "HW"

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

Change command line option passed to "firtool" due to upstream change.

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

Add an option to output using a "*.v" suffix.  This is still using the
CIRCT SystemVerilog back end, though.

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

- Add Maven release, Sonatype snapshots, and Javadoc.io badges
- Improve setup instructions

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

Add publishing to sonatype

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

Add --handover option to lower partially using SFC

Add a "handover" option that augments circt.stage.ChiselStage to lower
using a combination of the Scala FIRRTL Compiler (SFC) followed by
CIRCT.  The handover can be set at CHIRRTL (don't run the SFC), High
FIRRTL, Middle FIRRTL, Low FIRRTL, or Optimized Low FIRRTL.

Include tests of this behavior by looking at the
FirrtlCircuitAnnotation that exists before running CIRCT for different
handover values.

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

Add CI

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>