Add tool for building random tables

[benwebber]

Add tool to create random tables:

d10	Encounter
1	Spriggan
2–5	Owlbear
6–8	Wood elf bandits
9	Brown bear
10	Giant elk

Ideally, store this data as a dictionary tiddler so you could look up the effect:

{{tableData##1}}

Questions:

• How do we encode multiple effects or notes? Join multiple data tiddlers by the same keys?
• Should we encode ranges of rolls as individual roll/effect pairs? This would simplify looking up the effect by value.