Configuration management mechanism and initial settings variables

[mpatrou]

The code includes the addition of a configuration management mechanism.

Configuration settings are read from: CONFIG_PATH_FILE ,which defaults to: ~./shiver/configuration.ini .
If the file does not exist and/or variables are missing from the local configuration file, settings are retrieved from the configuration_template.ini file on the application startup.

Current settings added:
[generate_tab.oncat]

• oncat_ur; url to oncat portal
• client_id; client ID for oncat, which is unique for Shiver
• use_notes; boolean flag value to indicate the location of the names of the datasets (notes/comments vs. sequence name)

[main_tab.plot]

• title; plot title with options: full prints dimension data, name_only the workspace title, None: no title is printed in plots
• logarithmic_intensity; the flag indicates the plot scale (logarithmic or not)

[global.other]

• help_url; the url for the help buttons

The code has updated and additional tests for the mechanism and the settings variables added.

[rosswhitfield]

Appears to be working