We updated the Universal Relay Boilerplate to allow the use of databases other than Cassandra.

The Universal Relay Boilerplate, now at version 9.0.1 with the help of our contributors has been updated with the following changes:

• Windows compatibility has been added to the basic build scripts.
• React Native dependencies have been moved to dependencies instead of development dependencies to enable the use of react-native link.
• React has been downgraded to version 15.2.1 in order to lower the huge amount of warnings occurring in React Native.
• Express Cassandra has been upgraded in order to use the newly introduced support for migrations.
• All support for Cassandra has been moved into a separate unit, and URB in itself does not depend on Cassandra any more. It is possible to write units for supporting other databases.
• Bug fixes.

The same changes have been implemented in Rebar.