Remove all reads of `ReleephProject->repositoryID`

Summary:
Ref T3655. ReleephProject currently has both `repositoryID` and `repositoryPHID`, which point to the same object and are reudundant. Get rid of all reads of `repositoryID`.

NOTE: This makes project loads depend on repository loads. The eventual rule here will be that you must be able to see a repository in order to see projects for that repository, which seems like a reasonable rule. We might need to tailor it more than this (e.g., if there are branch read permissions down the line) but this seems like a reasonable minimum.

Test Plan: Grepped for `repositoryID` in `releeph/`. Called `releeph.getbranches`.

Reviewers: btrahan

Reviewed By: btrahan

CC: LegNeato, aran

Maniphest Tasks: T3655

Differential Revision: https://secure.phabricator.com/D6633
Remove ReleephProject->repositoryID writes

Summary: Ref T3655. Depends on D6633. This removes the writes and the column.

Test Plan: Created a project, edited a project. Verified the table doesn't have any keys including this column.

Reviewers: btrahan

Reviewed By: btrahan

CC: LegNeato, aran

Maniphest Tasks: T3655

Differential Revision: https://secure.phabricator.com/D6634
Remove "Project ID" from Releeph Projects

Summary:
Fixes T3660. Releeph Projects currently have an unused one-to-one mapping to Phabricator projects. This isn't consistent with other applications and has no integrations or uses. Get rid of it.

NOTE: Waiting for signoff from @legneato on T3660 before pulling the trigger here.

Test Plan: Created and edited Releeph projects. Grepped for references to project ID; there are a dozen or so but they're all either Releeph projects or Arcanist projects.

Reviewers: btrahan

Reviewed By: btrahan

CC: LegNeato, aran

Maniphest Tasks: T3660

Differential Revision: https://secure.phabricator.com/D6635
Remove "cut point commit identifier" from Releeph

Summary: Ref T3656. Releeph denormalizes branch cut point identifiers into Branch objects, but this information isn't useful or used for sorting, filtering, or enforcing unique constraints. Instead, derive it via noramlized pathways from the `cutPointCommitPHID`.

Test Plan: Ran storage upgrade. Ran `releephwork.getbranch` and `releeph.getbranches`. Grepped for `cutPointCommitIdentifier`.

Reviewers: btrahan

Reviewed By: btrahan

CC: LegNeato, aran

Maniphest Tasks: T3656

Differential Revision: https://secure.phabricator.com/D6636