Mat 425 add in OG-Izy wiring.

This PR is to be read in conjunction with https://github.com/OpenGamma/OG-Izy/pull/4: 
* It adds in the ability to link against OG-Izy.
* It adds an izy namespace and then demonstrates the pattern needed to add a single function binding from izy to the namespace, and then tests it.
* It adds the ability to accept multiple subprojects in `verinfo.py`. It then adds the necessary wiring to include the buildinfo yaml from `izy` into the OG-Maths master yaml.
* It updates the properties file to include the izy libraries in the jar.

Note: I'm not convinced of the API in the `izy` namespace as yet. I've simply added in the most obvious thing just to test that the code is wired up correctly and gives the correct numerical results. The `izy` namespace and functionality is subject to both autogeneration and multiple interfaces. IIRC the original OG-Maths had multiple interfaces to this library too, I expect the same will be required here.