Added skeleton for libnetcdf.settings.  See JIRA ticket at https://bugtracking.unidata.ucar.edu/browse/NCF-303
Added code to check for C Compiler.
First pass at fleshing out libnetcdf.settings for autotools-based builds.
Tweaked the libnetcdf.settings template file.
Roughed in skeleton of cmake support for libnetcdf.settings.
Continued to flesh out cmake support for libnetcdf.settings.  Added
a pair of functions which will return a yes/no depending on whether
or not a variable is defined.  By default, cmake uses TRUE/FALSE.
When creating the libnetcdf.settings file, CMake-based builds now include compiler and linker debug or release flags.
Merge branch 'ward-working'