MAINT: delete empty file.
TST: nose support and other cleanups in Matlab compat tests.
TST: nose support and cleanups in test_perfect_reconstruction.
TST: move tests to subdir of source code.
TST: add pywt.test() to run the test suite.
Merge branch 'nose-support' into master

Run tests with ``nosetests pywt`` or ``python -c "import pywt; pywt.test()"``.