Improve graph window

[DanicaSTFC]

Closes #336 #307 #312 #227 #322 #200 #170

• Adds pandas
• Creates classes to generate the tabs in the graphs window. In particular, the following tabs are created: SingleRunResultsWidget, BulkRunResultsWidget, StatisticsResultsWidget.
• Edits the results reader to be a numpy reader.
• Edits help text for the graphs.
• Adds docscrings to GraphsWindow.
• Improve way labels look, text style in the plots in the graphs window.
• Adds option in settings to edit the app fontsize to be user defined. Default is 12

The back-end code has been edited, some details are below:

• Edit argument of "RunResults"
• Use "data_label" instead of "plot_title"
• add attribute "self.run_name" in "RunResults"
• edit "self.title" in "RunResults"
• edit name of result argument in "SingleRunResultsWidget"
• use bar plot for relative freq plot.
• Edit graphs window title.
• Add file "manipulate_result_file"
• Edit tab title of single run
• add superclass
• Change "Summary" to "Bulk"
• Use pandas data frame to save data only once when making the plots.
• use the same methods in the bulk tab. Plotting the right amount of plots.

Single-run plots tab:

• Edit title to include run name and subvolume points and subvolume size
• Edit xlabels to include component
• Add units to xlabels
• Edit ylabels to be relative frequency, add units %
• Edit histograms to plot the relative frequency
• plot statistics on results.
• remove the for loop for the many tabs and use only one tab whit option to select what parameters to plot.

Bulk tab:

• Added functionality to pick parameters to plot
• Rewrote methods to be concise and reusing the single plots methods.
• removed matplot lib "plt" so it does work better without global variables (using Figure class).

Stat analysis tab:

• add mean and std in data frame. These will be passed to the classes and not recalculated again.
• Add new tab with statistical analysis
• Create class for stat analysis, with widgets.
• option to plot sub points or size.
• add option to collapse plots
• add option to plot all data in stat analysis with mean and std in same plot.
• edit color scheme

Tests

Installed and tested on a single run and also on a bulk run of points = 1000, 6000 and size = 30, 60, 90

Single tab:

Bulk tab:

Stat tab:

Opened new issues:

#340
#339
#338
#357