v1.7.0

ModelingToolkitStandardLibrary v1.7.0

Diff since v1.6.0

Closed issues:

• Add Mechanical/Translational libraries with both position and velocity based connectors (#109)

Merged pull requests:

• Adds permanent magnet DC machine (#49) (@ValentinKaisermayer)
• Start to Translational library with both Velocity and Position based connectors (#114) (@bradcarman)