Renamed RangeTree -> IntervalTree

This release contains a major name-refactoring and fixes the discrepancy between the conceptual interval tree that this package contains and the previous name RangeTree of the used classes, which is misleading. This update brings along a set of classes that are now called IntervalTree, while keeping all existing classes and only showing deprecation warnings when using the old RangeTree classes, along with instructions on how to transition to the new classes.

This version has no new features, so feel free to stay at version 2.0.1 if you prefer the name RangeTree or you do not want to spend time refactoring your codebase to fix the compiler warnings.

Upgrade to this version as an intermediate step before upgrading to 3.0.0 for a compiler-error free transition. This version will issue compiler warnings that you can simply fix by renaming the used classes as indicated by the warnings. As of 3.0.0, the RangeTree classes will disappear and break your code if you haven't transitioned to the new class name structure.