hdf5_ep

[svn-r19407] Purpose:
 Add --exclude-path option

Description:
 Merged from hdf5 trunk (r19406).
 Specified path to an object will be excluded from comparing the two files or two groups. If group is specified all the member objects will be excluded.
Related to "1890:  h5diff excluding object for file comparison via command line"

Tested:
 jam, amani