Added:
- axisValues() to AMDataStore.  This is the first step to having axis
values for all data relations.
- AMCDFDataStore will require a lot of testing.
- AMInMemoryDataStore will require testing but should be straight
forward.
Altered:
- Was accessing the data records instead of the axis value records.
Added:
- axisValues() to AMDataSource.  Now it needs to be added to all the
subclasses so it can be used  throughout the framework.
Added:
- axisValues() implementation to REIXSXESMCPDetectorPre2013
Added:
- axisValues() implementation to REIXSMCPDataSource.
Added:
- axisValues() implementation to AMRawDataSource.
Added:
- axisValues() implementation to AMProcessVariableDataSource.  Only
added to 1D and 2D implementations because 0D is a scaler with no axis
values.
Added:
- axisValues() implementation to AM1DExpressionAB.
Added:
- axisValues() implementation to ST0DTimestampAB.
Added:
- axisValues() implementation to AM0DAccumulatorAB.