Merge branch 'master' into other
Merge branch 'other'
Added Class `angle`.
Added more code for angles

added get_angle, new_angle, modified angle class and added 'angles':[]
to <figure>.things .
Merge remote-tracking branch 'origin/angles'
Changed add to append on line 164,165,166
Changed add to append on line 76
Merge branch 'angles' of github into congruency

Conflicts:
	prove.py
Merge branch 'congruency'