New goodies and bugfixes from 34 contributors! Thanks!
Includes Drush 9 compatibility, while keeping Drush 8 support. Thanks HongPong, joshi.rohit100, joseph.olstad, adamzimmermann, deggertsen, TravisJohnston, Gábor Hojtsy, nickonom, karolus, goose2000, andypost, bhagirajlimbu, Gerhard Roth, blakemorgan, kochertj, usurper, JamesOakley, Joehoe, upunkt, rdworianyn, mjkovacevich, tclnj, amitgoyal, bajah1701, TolstoyDotCom, erdm, kavo3, geek.merlin aka axel.rutz, marcel.krijthe!