Only throw omero.* exceptions from OMERO.blitz.

[jamoore]

Currently several java.lang.* exceptions are being thrown from OMERO.blitz. That results in exceptions of the form:

glacier2router: warning: dispatch exception: OutgoingAsync.cpp:144: Ice::UnknownException:
unknown exception:
java.lang.IllegalArgumentException: ome.model.core.Image does not specify a valid class.
        at omero.util.IceMapper.omeroClass(IceMapper.java:95)
        at ome.services.icy.util.IceMethodInvoker.handleInput(IceMethodInvoker.java:208)
        at ome.services.icy.util.IceMethodInvoker.invoke(IceMethodInvoker.java:152)
        at ome.services.icy.impl.Interceptor.invoke(Interceptor.java:112)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:176)
        at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:210)
        at $Proxy6.get(Unknown Source)
        at omero.api._IQueryTie.get(_IQueryTie.java:120)
        at omero.api._IQueryDisp.___get(_IQueryDisp.java:153)
        at omero.api._IQueryDisp.__dispatch(_IQueryDisp.java:455)
        at IceInternal.Incoming.invoke(Incoming.java:147)
        at Ice.ConnectionI.invokeAll(ConnectionI.java:2078)
        at Ice.ConnectionI.message(ConnectionI.java:1239)
        at IceInternal.ThreadPool.run(ThreadPool.java:788)
        at IceInternal.ThreadPool.access$100(ThreadPool.java:12)
        at IceInternal.ThreadPool$EventHandlerThread.run(ThreadPool.java:1248)

rather than nothing in Glacier and the following in the client:

omero.ApiUsageException
    serverStackTrace = ""
    serverExceptionClass = ""
    message = "ome.model.core.Image does not specify a valid class."
	at java.lang.Class.newInstance0(Class.java:350)
	at java.lang.Class.newInstance(Class.java:303)
	at IceInternal.BasicStream$DynamicUserExceptionFactory.createAndThrow(BasicStream.java:2048)
	at IceInternal.BasicStream.throwException(BasicStream.java:1450)
	at omero.api._IQueryDelM.get(_IQueryDelM.java:475)
	at omero.api.IQueryPrxHelper.get(IQueryPrxHelper.java:291)
	at omero.api.IQueryPrxHelper.get(IQueryPrxHelper.java:276)
	at ome.icy.model.itests.coverage.QueryTest.testGet(QueryTest.java:43)

Note: Add exceptions to LicenseAPI.ice

[jmoore]

Pushing back a bit, since this'll be general clean up.

[jmoore]

This also goes for the C++ client side code. We'll probably want to generate specific client-side (local) exceptions in Error.ice

[jmoore]

ClientErrors hierarchy added in Java and C++. It was difficult to make this work via Ice. Regular exceptions are checked, and local exceptions require local objects. Instead we'll have to do a language-specific hierarchy for each binding. Keeping the same names is probably a good idea.

There may be issues with who throws what, but this is looking much better.