3.0 composite key generation

Improve composite key generation and reflection. When doing some testing against Percona 5.5 I found issues with multi-column primary keys that spanned two integer columns. The columns would both be incorrectly labeled as auto_increment which would be rejected by XtraDB.

This set of changes adds an 'autoIncrement' option for integer & biginteger columns. This flag lets developer mark which columns should be treated as autoIncrement/serial. This feature does nothing in SQLite as it doesn't support multicolumn primary keys with auto-increments.