Intersection was previously not tested for singular ranges. This
ensures it will always work for singular ranges, too.
Tests: unit(dev)
Signed-off-by: Dejan Mircevski <dejan@scylladb.com>
1. Move tests to test (using singular seems to be a convention
in the rest of the code base)
2. Move boost tests to test/boost, other
(non-boost) unit tests to test/unit, tests which are
expected to be run manually to test/manual.
Update configure.py and test.py with new paths to tests.
