v0.3.0

This release adds <smart-column> parsing. From the inline help:

A <smart-column> is a shortcut for common column definitions. It must be of
the form <name>#<tag>#<tag>...

A <tag> adds either a data type or a constraint to a <smart-column>.

      #id
          Make this column the primary key. Omitting column type and <name>
          for an #id column creates an INTEGER PRIMARY KEY named 'id'.

      #text, #int, #float, #double, #datetime, #blob
          Set the column type.

      #unique
          Add a UNIQUE constraint.

      #null
          Omit NOT NULL constraint.