Add Xfce Terminal

[f2404]

Checklist for submitting a pull request to Terminals Are Sexy:

• [x] I have carefully read and comply with the Contributing Guidelines of this repo.
• [x] I have searched the PRs of this repo and believe that this is not a duplicate.

- **Title**: Xfce Terminal - **Link**: https://docs.xfce.org/apps/terminal/start - **Category**: Terminal emulator - **Description**: A modern terminal emulator primarily for the Xfce desktop environment

[f2404]

It seems we've got one endorsement, are more needed?

[k4m4]

Hi @f2404. Please squash your commits into one. Thanks!

[f2404]

@k4m4 Done!