[python-control-developers] [python-control/python-control] c1f5a9: DOC: add detail about StateSpace.dcgain

[Scott C. L. <sli...@cd...>]

  Branch: refs/heads/master
  Home:   https://github.com/python-control/python-control
  Commit: c1f5a9e06fa1cce06a859edcfb41b257ab772372
      https://github.com/python-control/python-control/commit/c1f5a9e06fa1cce06a859edcfb41b257ab772372
  Author: Scott C. Livingston <sli...@cd...>
  Date:   2017-01-08 (Sun, 08 Jan 2017)

  Changed paths:
    M control/statesp.py

  Log Message:
  -----------
  DOC: add detail about StateSpace.dcgain

Thanks to Rory Yorke (@roryyorke) and Richard M. Murray (@murrayrm)
for comments and suggesting text.

based on discussion at
https://github.com/python-control/python-control/commit/ee75d9aab7f36f565fb3ddb3c9699be6c2084173