First set of test cases for range trees.
linear.c is stub implementation so we can compile and write tests before
we actually implement the range tree.

The makefiles were modified just enough to get this to work, and have to
be cleaned up a lot.

git-svn-id: file:///svn/tokudb@1740 c7de825b-a66e-492c-adef-691d508d4ae1