added rough raster spec, and moved section 2 over
Updates for tile_table_metadata

Added in SRID to the tile table, put some questions in raster about how to make views from it.
moved some trigger wordage to safe geopackage
table and header alignment
clarification on the description of t_table_name
moved triggers sentences about tiles to safe geopackage
moved raster tables entirely over to raster spec
updates to metadata, refactoring raster