introduce a minimum size for clevel
initial sketeches of a BloscArgs object
introduce max and min clevel
prune whitespace
adding tests for the BloscPackHeader accessors
extract common parts of BloscPackHeader into a base class
first stab at using the BloscArgs object
debug the bloscpack header
shift the abstract stuff to an abstract module
shift more stuf into abstract object for better reuse

I should probably mention, that the tests are totally foobared now.
fix pformat
make test_append work with the new object
fix test_file_io.py
fix test numpy_io
fixup the command line tests, now that we have reused code
make much better use of the object oriented object
yay, an example of the new BloscArgs usage
fixup imports and indentation
clean up indentation
display with : instead of =