basic adder block

* low level add block takes 2 twos complement fixed point values and sums them with no latency
  returning full precision result.
* higher level adder block takes more parameters such as type of inputs, does necessary conversion
  to twos complement before input to add block.

TBD

* cast block to take care of quantization overflow etc before output if not full precision
* latency parameter addition for adder block
* use of vendor specific core to implement logic
* better automated test benches
list of requirements
basic badger palette scripts

badger_gen generated badger palette and adds it to the default palette
badger_block_gen is used by block scripts to draw and redraw blocks
inport, outport used as interfaces to non-badger blocks
add is a basic add block (meant to align with adder block in HDL library)

TODO

* look at finding common functionality during block operation
* more blocks
beginnings of xcos2verilog script