Added optional Create flags allowing easier use with POCO objects, "AutoInc" guids

Added optional Create flags allowing easier use with POCO objects

E.g. 
CreateTable<Stock>(CreateFlags.ImplicitPK | CreateFlags.ImplicitIndex | CreateFlags.AutoIncPK);

Will create a primary key on the Field Id, indexes on fields ending in Id and make the PK an autoinc.

Note.  I have created tests for this in the CreateTableImplicitTest.cs.  This will need to be manually added into your test project.

I have also added "autoinc" guids.  If a guid PK is marked as AutoInc then Guid.Empty will be replaced by a new Guid before inserting.

Additional tests have been placed in GuidTests.cs