Corrected "BAIL" macros to avoid infinite loop when logging is disabled and an
    error occurs after an "exit:" label.

Corrected a dozen Coverity errors (mainly allocation issues, along with a few
    other things):
        711711, 711802, 711803, 711905, 970825, 996123, 996124, 1025787,
        1047274, 1130013, 1130014, 1139538

Refactored internal fill-value code to correctly handle string types, and
    especially to allow NULL pointers and null strings (ie. "") to be
    distinguished.  The code now avoids partially aliasing the two together
    (which only happened on the 'write' side of things and wasn't reflected on
    the 'read' side, adding to the previous confusion).

    Probably still weak on handling fill-values of variable-length and compound
    datatypes.

Refactored the recursive metadata reads a bit more, to process HDF5 named
    datatypes and datasets immediately, avoiding chewing up memory for those
    types of objects, etc.

Finished uncommenting and updating the nc_test4/tst_fills2.c code (as I'm
    proceeding alphabetically through the nc_test4 code files).
Big clean up to type handling in libsrc4, which makes fill-values work
correctly for variables with string datatype, plus a few other minor changes.
Merge remote-tracking branch 'upstream/master'

Conflicts:
	libdap2/common34.c
	oc2/ocutil.c
Add a few cases for NC_CHAR type class that were missed earlier.
Merge remote-tracking branch 'upstream/master'
Switched CDash test location to the netcdf-staging branch.
Correct handling of variablen-length sequences for attributes, plus uncomment a
bunch of tests that stress this area of the library.

Also clean up some compiler warnings in the dispatch code.
Merge remote-tracking branch 'upstream/master'
Minor tweaks to comments and LOG messages.
Merge branch 'master' of https://github.com/qkoziol/netcdf-c into qkoziol-master
Reversed change to CTestConfig.cmake