Replace bitmap blit with ngfx blit

[Helco]

So this turned out to be quite a bit of work, I'll try to summarize the issues on the way:

• png loader: did not set free_data_on_destroy, thus the aggressive loading of the menu filled up RAM very fast
• png loader: the no-palette-but-alphas fix for 4Bit is also needed for 2Bit/1Bit palette bitmaps
• png loader: 1Bit uses lsb->msb bitorder, for now I opted for creating a palette (like with ^) and turning it into 1BitPalette
• app_manager: rwatch_neographics_init was being called quite often, dicussed temporary fix for this was moving the call into the overlay thread init (tracked in graphics context smashed pebble-dev/RebbleOS#62)
• menu: should set the compop to Set before drawing icons as to enable blending

[jwise]

Looks great to me. Does this depend on #130 and the resource change associated? If not, feel free to merge.

[Helco]

Yes, Tintin won't show any bitmaps without #130

[jwise]

Ok, add one more commit to this PR to update the submodule and then I'll merge the whole thing?

[Helco]

sure there you go

[jwise]

🎉