Move to local locking via bolt DB

[lkysow]

Changes

• not using Stash anymore for locking, using local BoltDB file or DynamoDB

BoltDB Architecture

Key/value database with a map from the LockID to the Run that's being locked:

Run how to identify this Run and which piece of infra it's locking

# value in the DB
type Run struct {
	RepoOwner  string
	RepoName   string
	Path       string
	Env        string
	PullID     int
	User       string
	Timestamp  time.Time
}
# key in the DB is a sha256 of `RepoOwner/RepoName/Path/Env`.

You need the ID to delete the lock.

Todos

• Delete endpoint /locks/:id and /locks/:id?method=DELETE for GET calls
• configurable hostname which can be used for the delete lock link
• Option to store locks in Dynamo DB
• repo hostname not hard coded
• config for where the database is stored
• fix UI
• remove mention of Stash for locking

Todos in subsequent PRs

• make detail view for locks and their plans
• add more tests