Added variable dicerolling (Fixes #3, #4)

- Added new elements to settings file (WriteSampleConfig.vb)
- Added diceroll limit checking (main.vb)
- Changed maxRolls and maxSides checking (chatStrings.vb)
- Updated chanMessage to show new variable maxRolls and maxSides
(chatStrings.vb)
- Fixed a slight grammatical mistake (chatStrings.vb)