by using the ADS::retrieveWS<Type>() method.

Refs #3269 I have included the option Efixed as a parameter when calling the algorithm ConvertSpectrumAxis because there was no way of specifying this before. I have updated the test files to take this new parameter into account. 

- Refs #3203: Implemented ISpectrum. It is the base class of EventList and Histogram and contains the spectrum number and list of detector IDs for a given spectrum.
- ISpectrum return X/Y/E vectors. EventList, e.g. calculates the histogram on the fly.
- Moved the EventWorkspace MRU list of histograms to be contained within the EventList; better code separation. Made a EventWorkspaceMRU class to encapsulate this more easily.
- Workspaces must implement getSpectrum (const/not const) to return a ISpectrum object. dataX(i), etc. methods on MatrixWorkspaces no longer need to be overridden since they call getSpectrum()
- Got rid of EventWorkspace::getEventListatPixelID() and doneLoadingData()
- replaceSpectraMap() methods offers backwards-compatibility with SpectraDetectorMaps by setting the specNo and detector list when called. Must be called AFTER creating all the spectra in a workspace.
- Refs #3318: maskWorkspaceIndex() implemented as part of ISpectrum.

Tell scons to build the new TestHelpers package so that ISIS buildservers are still happy with moving the test helpers while the CMake transition is still in progress. Refs #2196 and #1881

Rename Framework code directory to just that. Also delete Main and VS & Eclipse project file. Re #1881.

Add an algorithm, ConvertSpectrumAxis, to change the spectrum axis (the one up the side in MantidPlot) to something else. Currently, the something else can be anything you like, so long as it's Theta (of the detector relating to that spectrum). Re #753