Is it possible to use GPUImageLookupFilter in gpuimage2?

[wndzlf]

I have lut.png file and i wanna apply this png file to image by filter. but in gpuimage2 i can`t find GPUImageLookupFilter for lookuptable file. is it possible to use GPUImageLookupFilter in gpuimage2??

[zubco]

@wndzlf Look into #274