Aliases now use a hashtable. Aliases are now either commands or data.
Data aliases may be strings or raw bytes.
* Expand alias API
* Remove remote aliases - remote commands can still be aliased normally
* Update alias help text
* Fix an alias test and add new tests
* Add r_str_escape_raw() for null-safe escaping of unprintable characters
* Remove command to print alias without newline
* Fix dif command opening files as strings
25fc71570c