Merge pull request #80 from Workiva/release_r_tree_3.0.1

RM-225390 Release r_tree 3.0.1

Merge pull request #76 from Workiva/release_r_tree_3.0.0

RM-223965 Release r_tree 3.0.0

Merge pull request #74 from Workiva/release_r_tree_2.1.6

RM-222909 Release r_tree 2.1.6

Merge pull request #70 from Workiva/changelog-2-1-5

Update CHANGELOG.md

Bump version to 2.1.4

Bump version to 2.1.3

Bump version to 2.1.2

Bump version to 2.1.1

Bump version to 2.1.0

Bump version to 2.0.0