Remove key handling module.

Textadept's keys.MODE will be used instead.
Update copyright
Reorder docstring
Textredux indicators are defined as constants

Each defined indicator needs to be set using its own
`apply` function.
Update Textredux style module

Styles can be set using each style's apply method now.
Update docstring
Update docstring
Style matches in filtered list
Code cleanup and export module as table
Update docstrings and code cleanup
Code cleanup and module as table
Major Textredux buffer update

- code cleanup
- export module as table
- remove support for `on_keypress` (use `keys` instead)
- remove support for modifier keys for mouse clicks and keys (for now)
- don't use buffer.delete but io.close_buffer
Remove separate `Esc` key for closing

Alreadt set by default for all Textredux buffers
Use global translation table directly
Update for renames and changes in buffer module

Modifiers are no longer supported.
Add documentation for Ctags and colorise kind of symbols
Major Textredux list update

- code cleanup
- export module as table
- only `down` supported for showing more list items
- updates for changes in style module
Update LDoc generation config and templates
Add doc note about Ctags module
Update examples