In the help, specify or drop the unit for all angles

[AlMa1r]

On the front page https://github.com/galfar/deskew, we see the usage help containing

-a angle:      Maximal expected skew angle (both directions) in degrees (default: 10)
[…]
-l angle:      Skip deskewing step if skew angle is smaller (default: 0.01)

It's strange that the unit is given for -a but not for -l. By mathematical convention, an angle without an explicitly specified unit is assumed to be measured in radians. However, upon scrolling through the code for about 10 minutes, I think that degrees are assumed after -l.

Recommendation:

• either specify the unit in both cases in the help (in this case, consider degrees for -l; smaller units would also do, e.g., arcminutes or arcseconds),
• or skip the unit in both cases and assume that the user supplies the angles in radians.

In any case, interpret the two numerical values accordingly.