Added SimpleFilePathConverter class.

Performs file path substitution using StringUtils.replace().
This is basically the same as UnixToWindowsFilePathConverter but doesn't
change '/' to '\'.
BLVIII-25: Second user experiment - integrate XIA XMAP
In the new version of EPICs, the filepath in HDF file writer plugin 
uses fordward slash. A flag configurable in xml file was added to 
choose between fordward and backward slash without affecting other 
beamlines. By default, it sets up for the case of forward slash.
Merge branch 'gda-8.40' of ssh://dascgitolite@dasc-git.diamond.ac.uk/gda/gda-common.git into gda-8.40
Merge remote-tracking branch 'origin/gda-8.40' into gda-8.42
Merge remote branch 'remotes/origin/gda-8.42'