Version 0.10 changes (tracking issue) #917

This issue is intended to track changes that will be part of the version 0.10 release of python-control. This change in the minor version number will enable changes to the user interface, so this is a good time to make changes we have been discussing for a while:

Planned changes (and status):

• Add in the new multivariable interconnect functionality (done in Multivariable interconnect functionality #881)
• Get rid of support for the NumPy matrix class (no longer recommended by NumPy, though not yet deprecated; done in Remove NumPy matrix class #913)
• Restructure I/O system classes (see Releasing 0.9.4 and moving to 0.10.0 #904; done in I/O system class restructuring #916)
• Separate out plotting functions (see New plotting paradigm #645)
  • Time plotting function (initial, step, impulse, forced respond) (Time response plots #920)
  • Frequency plotting functions (bode, nyquist) (Update frequency response plots to use _response/_plot pattern #924)
  • Pole-zero plotting functions (pzmap, rlocus) (Update pole/zero and root locus plots to use _map/_plot pattern #953)
• Create factory function for flat systems (perhaps part of I/O system class restructuring #916)