Replacement Tokens - Numbered Args

Allow Simple Commands to have text replacement based on argument numbers.

**Example:**
```
CommandWord: !hug
Response: "Time for a big hug for $arg1!"

Input: !hug DevChatter
Output: Time for a big hug for DevChatter

Input: !hug @Brendoneus
Output: Time for a big hug for @Brendoneus
```

This depends on #3 being done first.