Changed manual picking procedure.

 - Adressed Issue #1 by adding a new fitting procedure
 - Adjusted format to remove most pylint/pycodestyle warnings

 - Added several new options to handle data sets with many samples.
 - New options allow to specify to how many samples a dataset should
   be downsampled to, either with or without filtering. The default is
   using no filtering, which leads to much faster computing times.

Fixed weird behaviour of bootstrap fitting for VST tests
Switched to scipy.optimize.curve_fit for this case.

 - Opening folders automatically creates a reloadable project config

- Added the possibility to get dilation data
- Replaced Savgol filter with median filter because of pick distortion
- Some minor formatting changes

The GUI Version is now fully functional and integrated into RST_Func.
To start the GUI-based picking use `python3 RST_pick_GUI.py`.
When using the default options it is equivalent to RST_main.py.

- Added more default options to the config.
-  Extended the `eval_shearstress` function by the option to review picks
- Changed the convention of DocStrings from single to double quotes.
- Added DocStrings to some functions.