EPICS - Add checkDroppedFrames to NDPluginBase
EPICS - NDFileImpl Add timeout to startCapure
EPICS - PVValueCache Class to act as buffer to EPICS.

putWait - send updates over channel access if the value to send is different from
the value in the IOC.

get - returns value sent in last monitor callback
EPICS - CachedLazyPVFactory - support use of PVValueCache
Zebra - support calls to set PULSE block parameters. Use PVValueCache
EPICS - FileWriterBase - support checkErrorStatus
EPICS - MulitpleImagesPerHDF5FileWriter - check for errors during scans
EPICS - Support fix exposure step size in flyscan
EPICs - EpicsMotor - use caputWait when setting the speed
Zebra - change logging level in isMoving