Modify WavefrontObject to allow '.' in group object names

Blender names objects with .001 ir .002 when separating vertices or duplicating objects and the importer would crash on them. This fixes the regex to allow dots in the name.
Fix slots being black due to vanilla blending leakage Forge fixes. Closes #1325 & #1242
Player sensitive version of Block.getPickBlock Closes #1348
Merge pull request #1376 from founderio/patch-1

Modify WavefrontObject to allow '.' in group object names
Fixes client-side fake rain

Changes the updateWeather function in WorldServer to only send the
weather info to players in the correct dimension, rather than all
players on the server. This is what causes the client-side rain, as the
client believes that it has started raining locally, rather than in
another dimension.
Merge pull request #1492 from XCompWiz/clientrain

Fixes client-side fake rain