A new formula function for creating a VImage

[shroffk]

A simple formula for creating a VImage.

In the past we had many many scripts to handle channel access images
=imageOf(array_data, height, width, ...)

[kasemir]

Bummer... Should these be removed?

import org.epics.pva.data.PVAByteArray;
import org.epics.pva.data.PVADoubleArray;
import org.epics.pva.data.PVAFloatArray;
import org.epics.pva.data.PVAIntArray;
import org.epics.pva.data.PVALongArray;
import org.epics.pva.data.PVAShortArray;

They're not used inside the new function, which makes sense because the function deals with VType data, not the underlying PVA... types.
So no need to import org.epics.pva.data.....
In fact must not do that, because now I get a build error:

[javac] 
..../phoebus/core/formula/src/main/java/org/csstudio/apputil/formula/areadetector/ImageOfFunction.java:11:
error: package org.epics.pva.data does not exist
    [javac] import org.epics.pva.data.PVAByteArray;