Static build year (rebased onto dev_5_0)



This is the same as gh-2149 but rebased onto dev_5_0.

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In a follow-on from gh-2173, the year shouldn't be completely dynamic, but rather generated at build time.

Testing in Python:
```
$ bin/omero shell
In [1]: from omero_version import build_year
In [2]: print build_year
2014
```

In the web, "© 2007-2014 University of Dundee & Open Microscopy Environment" should be shown.

@will-moore should be happy with the code.