removed includes in the fCWT library that are not used (or imported in the example anyway)
instead of building the mex files, the benchmark and the example from the fCWT source, link them with the fCWT library directly
the library directory for the python build points to the sources, but not the libraries (similar to the previous pull-request #26 <- feel free to close that one)
additionally, the hidden macOS files .DS_Store and the pycache folders are removed and added to a gitignore file.
@fastlib I cleaned up the code a little.