Log Message:
neomutt: update to 20200925.

2020-09-25  Richard Russon  <rich@flatcap.org>
* Features
  - Compose: display user-defined headers
  - Address Book / Query: live sorting
  - Address Book / Query: patterns for searching
  - Config: Add '+=' and '-=' operators for String Lists
  - Config: Add '+=' operator for Strings
  - Allow postfix query ':setenv NAME?' for env vars
* Bug Fixes
  - Fix crash when searching with invalid regexes
  - Compose: Prevent infinite loop of `send2-hook`s
  - Fix sidebar on new/removed mailboxes
  - Restore indentation for named mailboxes
  - Prevent half-parsing an alias
  - Remove folder creation prompt for POP path
  - Show error if `$message_cachedir` doesn't point to a valid directory
  - Fix tracking LastDir in case of IMAP paths with Unicode characters
  - Make sure all mail gets applied the index limit
  - Add warnings to -Q query CLI option
  - Fix index tracking functionality
* Changed Config
  - Add `$compose_show_user_headers` (yes)
* Translations
  - 100% Czech
  - 100% Lithuanian
  - Split up usage strings
* Build
  - Run shellcheck on hcachever.sh
  - Add the Address Sanitizer
  - Move compose files to lib under compose/
  - Move address config into libaddress
  - Update to latest acutest - fixes a memory leak in the unit tests
* Code
  - Implement ARRAY API
  - Deglobalised the Config Sort functions
  - Refactor the Sidebar to be Event-Driven
  - Refactor the Color Event
  - Refactor the Commands list
  - Make ctx_update_tables private
  - Reduce the scope/deps of some Validator functions
  - Use the Email's IMAP UID instead of an increasing number as index
  - debug: log window focus