Improve TreeSelection classes naming

[Christopher Keil]

USE CASE: WHAT DO YOU WANT TO DO?

Rename TreeSelection related classes.

STEPS TO REPRODUCE AN ISSUE (OR TRIGGER A NEW FEATURE)

-

CURRENT BEHAVIOR

Names of TreeSelection classes, in particular the interface, are unclear.

EXPECTED BEHAVIOR

The names represent the purpose of the classes well and follow typical conventions.

DEVELOPERS ONLY SECTION

SUGGESTED CHANGE (Pseudocode optional)

e.g. Add a color selection class

FILES AFFECTED (where the changes will be implemented) - developers only

TreeSelection.java and related classes

LEVEL OF EFFORT - developers only

trivial

COMMENTS