gitignore .pyc files
fixed typo in variants.py
removing variant staves (staff and staffDef elements)
introduced test script and removed test code from transform.py

Multiple test can be run by defining specific test cases in
transform_test.py
execute
> python transform_test.py
to run all test cases.
fixed typos in test case execution
print orig file name at the beginning of each test case
FIXED: some empty <lem> elements
ignore test output files
basic test case for transforming variants
fixed some bugs in skip-dur calculation
fixed name of test case Variants.01
added test case for whole-measure <app>
more simple test cases:

- rhythm different rhythm
- multiple variant in a single measure in different sources
- fixed a typo in measure numbers
working on variant trasnformation