Pytest-tui

- Fixed minor issue with start/stop regex folding algorithm, where the start and stop markers were being printed in the output.
- Added foldable output to individual test cases.
- Fixed issue 110, where tui_files/ folder was getting created all over the place.
- Change `requirements/` directory to `reqts/` to avoid confusion with `requirements.txt` file.

- Removed `--tui-fold-level` option, now replaced by modified ``--tui-regexfile` implementation (previous bullet point); allows for regex(es) to be specified in a file, rather than on the command line.
- Fixed Issue 100 (obviated by previous change in fold behavior).
- Changed output files folder to ./tui_files.
- Added new buttons to About tab to remove/restore/invert colors.
- Introduced tests to test the plugin itself, using pytest's 'pytester' fixture.
- New buttons in HTML report to invert/remove/restore colors.
- Added Faker library to standard dependencies.

- Added new folding mode `--tui-fold-regex`. This mode allows specifying reg-ex's marking the beginning and end of a section that the user wants to fold. See README for details.
- Bumped `rich` library version to 12.6.0 to allow for use of SeleniumBase library during testing.
- Fixed issue 100, where if the user does not specify the `--tui-fold-level` option, the HTML report will not render individual test cases correctly (they won't open/close when clicked). `--tui-fold-level ` is still supported but now if user does not specify it, the level defaults to WARNING, and displays the new Folded Output section anyway.
- Added comprehensive HTML page testing using SelniumBase.
- Fixed minor issue with bash test script not installing faker lib.
- Fixed exception issue when specifying non-default output filename for HTML report.

- Re-implemented the folding feature for HTML report. This version doesn't rely on the user having to do anything with their tests other than smartly partition their log statements into the proper debug levels for their application (i.e. no clunky logfile shananigans). The folding feature automatically folds all consecutive log statements that are less than a configurable level. This is controlled with new command line option '--tui-fold-level'. Also, there is a new 'Actions' button in the HTML which folds/unfolds all fold sections.
- Fix sticky issue with topbar.
- Pin requirements with pip-tools.

- Added initial implementation for foldable HTML lines (see docstring on class TuiLogger in tui_logger.py for details). This feature is experimental.
- Minor improvements to HTML report "About" page.

- New command-line option `tui-reportfile`, which allows user to specify the name of the HTML file produced when the console script `tuih` is run.