v0.2

This v0.2 release supports all of the previous config variables and adds camera support.

ENABLE_CAMERA=1/0 (1 to enable, 0 to disable)
GPU_MEM=XXX (in MB. If not set and ENABLE_CAMERA=1, this will default to 128 which is the min. required for enabling camera support)

Add fix for pi-gen trying to use empty Wi-Fi vars