Consolidate coverage options

 - Remove Makefile.coverage.in
 - Drop BUILD_COVERAGE_ON_DEBUG for ENABLE_COVERAGE_REPORT (defaults to
    on if included)
 - Add clean-gcda target

this is required for dcmctrl7 config

This will be used unless overriden in doocs server conf

This fixes issues when using LaTeX in doxygen

This can potentially be a severe performance issue, if an application has many persisted large arrays.

Improvement8453 drothe large array persistency

- arrays are now by default saved just like spectra
- Short arrays go into main server config file, long into separate files
- only if array is writable
- behaviour is configurable in order to return to default behaviour of
DOOCS

- add new elements
- add persist element
- make definition less dependent on ordering in XML file
Now, all but one test xmls validate, and the one exception should
actually not do so.

Previous attempt to work around the tine linking issue did not work.

This is a work around for not finding libtinemt at runtime. The DOOCS serverlib is lacking the RPATH, hence its dependencies are not found. If clientlib is linked first, tine is already linked.