Initial commit for ibus-rime, version 1.5.0

Summary:
Fixes T1001.

Depends on D12533.

Initial commit for ibus-rime, the Rime Input Method Engine for Linux/IBus.

Test Plan:
Tested typing, settings overriding, and custom input schemas.

Note: it has been tested on Budgie DE. Other DEs are not tested (I don't have enough hardrive space to do so. I build almost everything with GitHub Actions or a small AliCloud 2-core VM).

Signed-off-by: Gavin Zhao <gavinzhaojw@protonmail.com>

Reviewers: Triage Team, Girtablulu

Reviewed By: Triage Team, Girtablulu

Subscribers: Girtablulu, JoshStrobl

Maniphest Tasks: T1001

Differential Revision: https://dev.getsol.us/D12534