Shortcuts to reduce the labeling time.

[frankool]

Point +, Point -, Rect....to add shortcuts to this functions can be helpful for fast labeling. Including add shape to label only pressing a number from example. Mapping the classes to numbers and pressing only the number the shape can be added to this class, every time that i create a shape i spend more time refining and selecting the class of the shape. Thanks for the effort.

[vietanhdev]

This pull request added Q, E for points: https://github.com/vietanhdev/anylabeling/pull/98