v0.4.1: spopt: a python package for solving spatial optimization problems in PySAL

What's Changed

Facility Location

• Check feasibility following solution attempt by @jGaboardi in #239
• Document locate class properties by @gegen07 in #243

Other Changes

• add spopt ref to JOSS paper by @jGaboardi in #245
• cleaning up JOSS manuscript -- references & links by @jGaboardi in #247
• address reference concerns, etc. [2] by @jGaboardi in #249
• clean out code block and add preexisting facility text by @jGaboardi in #250
• a 'final' proofing for JOSS manuscript by @jGaboardi in #252

Full Changelog: v0.4.0...v0.4.1