Rework latest chains into properties, with improvement.
Made some methods static.
Rework seed selection and subsequent sentence building (made it
IEnumerable again). Also change WordCount a bit.
Fix latest chain properties, simplify WordCount property and make it deduce the order from the passed initial chain.
* BrainFrontend.cs: Modify comment slightly.

* Database.cs: Correct SentenceConstruct invocation and modify
  CreateSeedSql to match even more initial chains.
Rearrange SmartIrc4Net options.