Convert make scripts (mkpkg.sh) into Makefiles

[olebole]

This concentrates all settings required to do the build in the Makefile itself, and removes any dependency of a specific shell. At some later point, we may add a make install, which could install IRAF to a standard place (like /usr/local/lib/iraf, removing the need of the ./install script, and making IRAF much more conform to todays standard installation procedures.

Available targets:

• make all (or make sysgen); default - build the full system. Steps:
  • make arch - Prepare the system for the given architecture
  • make bindirs - Create directories to hold the binaries.
  • make novos - Bootstrap first stage: build tools without the Virtual Operating System (VOS)
  • make host - Create VOS and rebuild the build tools
  • make vendor - Build the 2rd party libs (votable, cfitsio)
  • make core - Build the core package system
  • make noao - Build the NOAO package
• make clean - removes all binaries, object files, and copied include files
• make test - Run the test suite

The change also makes it possible to compile IRAF without architecture specific bindirs, i.e. directly to bin, unix/bin, noao/bin, by invoking with a defined but empty IRAFARCH, i.e. IRAFARCH= make

Proposed roadmap:

• make install - Install IRAF to the standard system place (/usr/local/lib); should be configurable (f.e. prefix=/opt)
• make config - Configure the current place for local use (replaced the ./install script)

Drawbacks: mkpkg does not build the vendor packages anymore (but make does)