makes indents more important; adjusts tmLanguage

1. Indents are more important, e.g.

    ```
    Pr0:
      ☐ t0
    ☐ t1
    Pr2:
      ☐ t2
    --- ✄ -----------------------
      ☐ t3
    ```

    t1 doesn't belong to Pr0, t3 doesn't belong to Pr2.
    t1 and t3 aren't in any project, thus they shan't get `@project` prefix.


2. I saw you made some changes into tmLanguage, but it doesn't work for me (assumed all tags should be greyish), thus I made some changes.


Could you please try it and let me know if something wrong?