Support ranged word wildcard matching

[kirsle]

Support an extended syntax for wildcard characters in triggers to enable them to match ranged numbers of words, for example one could match "between 2 and 4 words" or one could be "no more than 3 words" and so on.

Syntax example:

// match 2 words (first and last name)
+ my name is *2
- Nice to meet you <formal>.

Types of ranged words to support:

• * = match one or more words (current behavior; no change) -- regexp equivalent (.+?)
• *5 = match exactly five words -- regexp <word>{5} where <word> is like (?:\b\w+\b[\s\r\n]*)
• *~5 = match one to five words -- regexp <word>{1,5}
• *2~5 = match two to five words -- regexp <word>{2,5}
• *2~ = match at least two words -- regexp <word>{2,}