Use "annotate" rather than "blame".
Improvements to completion code.
Completion types are now represented by symbols.
Standardize on singular: avoid p4-branches-completion vs. p4-branch-string-completion.
Each completion type has its own structure that brings together all the information about how to fetch completions from the depot.
The association list p4-all-completions avoids code duplication: can iterate over or search on this list instead of copying out code for each completion type.
Each completion cache entry has a timestamp, and stale entries are purged before looking up anything in the cache. This avoids the need to maintain a cleanup timer, and ensures that recently fetched results remain available even as stale entries are purged. Fixes #12.
Completion types use more specific Perforce commands to avoid requesting unnecessary items from the server. Fixes #10.
Use completion-table-dynamic to simplify completion building. Fixes #53.