Irida-sistr-results

* Added additional column to report **Reportable Serovar Status** used to indicate serovars that are considered as reportable by SISTR.
* Disable with `--exclude-reportable-status`. Override list of reportable serovars with `--reportable-serovars-file`.
* Saving the command-line string to the exported file.

* Changed code to conform better to Python packaging standards.
* Moved location of `config.ini` file so it gets properly included in Python package.
* Add command-line option `--workflow` to export SISTR results from specific versions of the IRIDA SISTR workflow.
* Add command-line option `--samples-created-since` to export SISTR results from samples created since a particular date or the passed number of days ago.

* Fixed performance when exporting SISTR results. Previously, user-run SISTR analyses where included in the results by default, but these took a significant amount of time to export. Now, only automated SISTR analyses and analyses shared with a project are included by default in the final results. To revert back to the previous behaviour, you will have to use the `--include-user-results` command-line option.

* Fixed bug where a user has access to a shared analyses to a project but not access to the samples, causing a failure for all results.
* Removed printing of JSON reponses on use of `--verbose` flag.

* Added ability to set a config file using `--config`.
* Fixed broken loading of configuration file located in `~/.local/share/irida-sistr-results/config.ini`.
* Other small error message fixes.

* Display URL of IRIDA instance and updated some text on the screen.