added the tree functions and tests
treea946f572fc3c9f6cbaef60331a2c6ef7db2b86f1
-rw-r--r-- 24 History.txt
-rw-r--r-- 1082 LICENSE
-rw-r--r-- 4403 README
-rw-r--r-- 1092 Rakefile
-rw-r--r-- 263 TODO
drwxr-xr-x - doc
drwxr-xr-x - lib
drwxr-xr-x - tests