Add INSTALL target to Makefile

The common 'make install' target takes on the responsibility of moving
the recently compiled program and its associated man-docs to
directories where they can be accessed and run by all cmd-line users.

The 'install' target for cQuist is little different.

As a side note, until a short local configuration script is written,
the command can still only be run from the project bindir (because
certain config files and log files are looked for in relative paths.

This limitation (see above), will soon be overcome by changing the
expected location of the config files to a hidden directory in the
user's home directory.
Remove cpy-paste remnant