Add "afe_" prefix on custom block prefix name for Select2Type form

I believe this will fix issue #92
Merge pull request #96 from Restless-ET/patch-1

Add "afe_" prefix on custom block prefix name for Select2Type form
[FIX][afe_knob] bgColor not passed + autoescaping
[FIX] Collection upload in synchronous mode may cause a fatal error.