Broadworks-ocip

Feature
* Note that this is now based on the R25 schema ([`6cb821b`](https://github.com/nigelm/broadworks_ocip/commit/6cb821b04974cbbb25f3700912b09baf2410e85a))

Fix
* Quiet linter warnings ([`6c3f5ce`](https://github.com/nigelm/broadworks_ocip/commit/6c3f5ce2b1dba7852594682ceb966b2d79d8e69b))
* Ensure SearchCriteria are not seen as Requests ([`6a9c35e`](https://github.com/nigelm/broadworks_ocip/commit/6a9c35e590600f5fce73f19faa4f3bc53fa2f331))

Documentation
* Update README for recent changes ([`7cb3354`](https://github.com/nigelm/broadworks_ocip/commit/7cb335431a625bf5b15c464b1d66253dc9127411))
* Mention the Null object - its important ([`2f1e047`](https://github.com/nigelm/broadworks_ocip/commit/2f1e0478c159eadff9d201477e722b5f1dd01017))

Feature
* Add Null value which stands in for a forced XML nil value ([`4701ec5`](https://github.com/nigelm/broadworks_ocip/commit/4701ec529b3ce35f183d41e30c3c9ab7bb90f701))
* Handle nested elements ([`2467b8f`](https://github.com/nigelm/broadworks_ocip/commit/2467b8fc5edd7c0550b68af94997b5225a1d4485))

Fix
* Table decoder handles weird chars in column names ([`a8fe66b`](https://github.com/nigelm/broadworks_ocip/commit/a8fe66b791e90024e2d884c567985818ce2e96e3))
* Fully handle NULL and empty lists ([`2f5f590`](https://github.com/nigelm/broadworks_ocip/commit/2f5f5904c1d0339443491652ef6df9bc27720ff3))

Fix
* Make abstract types work now I have an example ([`5bff15c`](https://github.com/nigelm/broadworks_ocip/commit/5bff15c332f705c079944ff89e3e4125278289f5))
* Second attempt to handle abstract classes correctly ([`63f1454`](https://github.com/nigelm/broadworks_ocip/commit/63f1454ec448660145f2c012185a5ffc258fcfdb))
* Handle abstract types ([`84abaa2`](https://github.com/nigelm/broadworks_ocip/commit/84abaa29ccf4b95f9db60c0e5dcfdfcfaccc4aff))

Fix
* Reinstated type checking now hierarchy in place ([`6f99654`](https://github.com/nigelm/broadworks_ocip/commit/6f99654a4a3991c527d9ad42035f84a5732f6da4))
* Regenerate broadworks classes ([`faf3b1b`](https://github.com/nigelm/broadworks_ocip/commit/faf3b1b90cc19d902b9b9623946e92ca16f5401d))
* Add class hierarchy information into generated classes ([`f9eb352`](https://github.com/nigelm/broadworks_ocip/commit/f9eb352abf899e62c9bcac870cbc553aae205d26))