SQLite - avoid cache well defined views.

[romicadascalescu]

There are cases when views are simple views and SQLite provider can detect the main class and use the spatial index of the main class. Rules:

• Table and main property names needs to be provided in a case sensitive way.
• Primary Key of the view needs to be added in fdo_columns as read-only (fdo_data_details = 0x02)
• All not well defined property of the view need to be added in fdo_columns providing the right type (e.g. 'test' as TEST_COL).
• The geometry property of the view needs to be added in geometry_columns