Depend on ngcp-db-schema >= 3.0.0~ to satisfy trunk builds

This fixes the failing daily builds, where ngcp-config-{ce,pro}
depends on ngcp-db-schema >= 3.0.0, but ngcp-db-schema is provided
only as 3.0.0~1368026494... currently.

debian/control

@@ -9,7 +9,7 @@ Homepage: http://sipwise.com/
 Package: ngcp-config-pro
 Architecture: all
 Depends: ngcp-cfg-schema,
-         ngcp-db-schema (>= 3.0.0),
+         ngcp-db-schema (>= 3.0.0~),
          ngcp-ngcpcfg,
          ngcp-ngcpcfg-ha,
          ngcp-templates-pro,
@@ -23,7 +23,7 @@ Description: Metapackage for NGCP platform configuration system
 Package: ngcp-config-ce
 Architecture: all
 Depends: ngcp-cfg-schema,
-         ngcp-db-schema (>= 3.0.0),
+         ngcp-db-schema (>= 3.0.0~),
          ngcp-ngcpcfg,
          ngcp-templates-ce,
          ${misc:Depends},