Description of the feature

Suggested by @ovari.

Allow users to quickly enter categories by utilizing ":" to jump to the end of the autocomplete string. This allows them to type in the minimum number of characters to select the category & subcategory.

Use cases

Particularly useful in conjunction with #1477.
For example, suppose I have the category Income:Investment Income:Dividends:Qualified.
This could be entered by typing "i:i:d:q" (minimally, if they are all the first alphabetically).