Improve parsing of field tokens

Bracket characters are no longer stored as part of the field name in a
variable node. Brackets are still part of field tokens while they're on
the token stack, however.
Add to autocomplete component/demo

The autocomplete component now properly loads suggestions based on the
cursor's current context. Nothing is displayed at the moment, however.
The next step is to filter suggestions to match the current token, and
then display everything. Finally commands must be hooked up to make
everything run as desired.
Add suggestion filter to autocomplete

Filter autocomplete suggestions based on the text to the left of the
cursor.
Complete instruction/suggestions details divs

Created functions to manipulate the divs containing the list of
autocomplete suggestions and instruction details
Add functionality for using selected suggestion
Add custom commands

Begin work on adding custom key commands for autocomplete. Lots of bugs
at the moment.
Fix autocomplete bugs

Fixed several bugs dealing with hiding and showing the autocomplete list
Add function to replace text at cursor

The build in method for replacing words bordering the cursor has some
undesirable behavior when next to non-text characters.
Example, the current line of text looks like this:
B_myBool =|
(the pipe represents the cursor) When autocompleting with the build in
replace method, the '=' gets treated as a word and is consumed:
B_myBool mySuggestion
instead of:
B_myBool =mySuggestion
The same happens with brackets, parens, single space/tabs, etc.

This issue has been fixed with a custom word selection function that
will not pick up special characters/space
Add commands to autocomplete

Add commands to use the active autocomplete suggestion.
Autocomplete activates the selected item with the following keys:
tab, space, enter, (, ), [, ]
Done with autocomplete (for now)

I believe the autocomplete component is ready to go.
It still lacks implementation for fielded items, but aside from that, it
is a fully functioning product!