grex-1.4.5-bp160.1.14

- Modernized rust in specfile and enabled tests
- Update to version 1.4.5:
  * All dependencies have been updated to their latest versions
  * For a small set of special characters, grex produced incorrect
    regular expressions when the case-insensitivity feature was
    enabled. This has been fixed.
  * The code for creating regular expressions in verbose mode has
    been simplified and is more performant now.

- License correction based on legaldb scan

- Update to version 1.4.4:
  * All dependencies have been updated to their latest versions.
- Python library excluded from the package by changes to --features

- Update to version 1.4.2:
  Improvements:
  * All characters from the current Unicode standard 15.0 are now
    fully supported.
  * A proper exit code is now returned if the provided user input
    cannot be handled by the CLI.
  Fixes:
  * Several bugs have been fixed that caused incorrect expressions
    to be generated in rare cases.
- Removal of unneeded _constraints

- Initial spec for grex 1.4.1