Fix NPE in canvas bag recipe

NPE occurs when other dye using recipes (eg recipe for lumar) are used.
Lamps, Lamps, Lamps, Lamps and inverted lamps
Merge branch 'master' of github.com:Quetzi/BluePower
-Added more Sorting Machine GUI stuff.
-Added generic GUI widget handler.
-Added more Pneumatic Tube logic (still not finished!)
Final buffer fixes and added recipe
Merge PR from fabricator77
Fix imports
Fixed build
Fix Igniter texture
Pneumatic Tubes are working!!!! :D
Todo still: cache testing and color handling
Refactoring on the tile caching in the Machine Base, also added Sorting Machine logic (still needs testing, and is redundant atm).
TileEntity caches now update... >.<
Redbus GUI, floppy disk item
minor changes to computer TEs
Fix text formatting issues
screwdriver ignores CPU for redbus GUI
Update untextured.txt
Missing/require textures for computer blocks/items
Merge pull request #43 from fabricator77/master

Computer redbus GUI changes
Merge pull request #39 from fabricator77/patch-1

Fix NPE in canvas bag recipe