Flashfocus

- Flash parameters can now be set for specific window class/ids. Regexes are supported.
- A faster alternative to the flash_window script (`nc_flash_window`) was added which requires openbsd-netcat. This script is not fully supported yet, so don't be surprised if it disappears later.
- Added a new `flash-on-focus` parameter for windows which user does not want to flash on focus but still needs the ability to flash on request.

- Improved logging output

- Added a basic configuration file.
- Deprecate --opacity parameter, --flash-opacity should be used instead.

Fixed
- Uncaught WindowError when window closed during flash.

Added
- Ability to flash window on keybinding with flash_window command.

Changed
- Window conflict behavior changed. Previously, if two flash requests were made for a single window within the flash interval, the second request would be ignored. Now the first request is just restarted, which makes the program feel more responsive.
- Removed tendo dependency.
- Added the default-opacity parameter.

Fixed

- Division error in the python2 version which lead to 1ms flashes by default.