Extend the JiraSoapAPI to provide ways to create and modify filters.

As part of our in-house application release cycle, we need to select issues for release notes. However, our development process does not lend itself to using versions. Instead we use filters with date filters. We would want to create a filter as part of the build automation process but the current JiraSoapAPI does not provide such a capability.

An API similar to the Hibernate way of creating HQL criterias would be very useful