3.0 sqlite create table

Add basic support for creating tables with sqlite. I've implemented many of the same things that exist for MySQL. Some notable changes:

* Removal of `charset` and `collate` from fields. These are properties are only useful in MySQL and only in legacy/non-standard schemas. I don't think it is worth the candle to continue supporting these.
* Add/fix decimal/float precision. I missed this the first time around and it is necessary for decimal/float columns.
* SQLite supports far fewer index types. Unsupported indexes will be silently omitted from the generated table SQL. I felt this made the schema system more flexible than only allowing supported index types.