Add `angularFrame `and `qSpaceFrame` to Frame Python API

Implements Frame transformations between q and angular coordinates.

Datafield::crop is repaired.

Couple of assertions was removed from projections; they often fail due to rounding error.

requested review from @j.wuttke

assigned to @m.svechnikov

approved this merge request

added 2 commits

• 48ee72c4 - rm {}
• 7a1bcdd0 - rm Coordinate()

Compare with previous version

resolved all threads

merged

mentioned in commit d46c9374