NoC Congestion optimization options are not listed in the VTR docs

[vaughnbetz]

Most NoC command line parameters are explained in the VTR docs, but the congestion algorithms aren't. Please add them.

[soheilshahrouz]

#2766 updates command_line_usage.rst file with new NoC routing algorithms. Is there any other files that need to be updated?

[vaughnbetz]

Thanks. Lost track of that one; merged it now so closing this.