1.2.1

Client:
-Added a Classic-style Nether dimension for Classic worlds.
-Added /weather command
-Creative players extinguish from being on fire instantly upon stepping off of lava/fire
-Cob-webs and fluids no longer push Creative mode players when flight is activated
-Fixed rare collision issues
-Fixed certain music discs no longer playing as expected
-Fixed Ghasts no longer obeying mobgrief gamerule
-Fixed Ghasts attacking Creative mode players unprovoked

Server:
-Added a Classic-style Nether dimension for Classic worlds.
-Added /weather command
-Creative players extinguish from being on fire instantly upon stepping off of lava/fire
-Cob-webs and fluids no longer push Creative mode players when flight is activated
-Fixed Ghasts blowing things up with fireballs when mob griefing is disabled via gamerule
-Fixed Ghasts attacking Creative mode players unprovoked