Fix syntax error in schema script serial is a data type, just like int, and only one can be given. In passing use the standard conforming way to specify the auto-generated column and make it the real primary key.

#-*-makefile-*-
# Authors: Sascha Wilde <wilde@intevation.de>

.PHONY: all dependencies clean

all:	dependencies
	yarn build

dependencies:
	yarn install --check-files

clean:
	rm -rf ../web