Change deps for "cqlmm" Makefile target.

Instead of specifically looking for .go files in cmd/cqlmm and config,
just look for them in ".", recursively.
Add the CreateCQLMigration func.

This function will create a new migration file using the nomenclature:

	$CQLMM_MIGRATIONS_DIR/migrations/$UNIXTIME_$NAME.cql

This function is in the github.com/nesv/cqlmm package, and will be
imported by the github.com/nesv/cqlmm/cmd/cqlmm command.
cmd/cqlmm: Implement the "create" command.

This is the command line for creating a new migration:

	$ cqlmm create MyNewMigration cql

You must specify "cql" at the end of the command, as this will enforce
intentional call signatures in the future, and allow for future support
of writing migrations in Go. Forcing the user to specify "cql" at the
end of the command (to specify the migration type) prevents any weird
"gotchas" from happening due to default behaviours.
Merge pull request #4 from nesv/create-command

:shipit: