Fixed typo in advanced IPython notebook
Allowing '/' as a path separator in Windows
Relabeled "arguments" as "parameters" in the documentation
Multiple changes:

- Added ability to read Dymola *.txt simulation results
- Removed optional functions to Variable.values(), Variable.times(), etc.
- Added explicit file extension (*.mat) in advanced IPython notebook
- Improved computational efficiency while loading and analyzing simulation results
- Added next_nonblank function to util module
- Improved documentation
- Cleaned up code