MIR Central Test Node DICOM Software Code

Replace reference to DCM_UNKNOWN with DCM_UN.

Add #include "ctn_os.h" and comment out other system includes.
This leads to a more uniform way to handle system includes and
makes changes easier (at the expense of include extra files you
might not want).

Change LIBS_CTN to LIBS_CTN_NODB.

Add install-clean target: Does the install and then cleans the directory
when done.

Initial revision

Indent changes.

Add code to initialize/shutdown threads.

Add second argument to dcm_dump_file.

Replace use of old macro (ERROR) with new macro (CTN_ERROR).

Cosmetic changes to satisfy lint.