[AD] Makefile generic install rules

[Eric B. <ebo...@li...>]

The attached patch factors out the generic makefile install/uninstall rules 
into makefile.all for the non-Unix ports.  This saves a bunch of duplicated 
code.  It also adds the few missing dependencies spotted by Grzegorz.

Tested with DJGPP, OpenWatcom, MinGW/MSYS, Borland C++ and BeOS.
Untested with MSVC, MacOS X and QNX.

Applied to mainline and, since the patch for mainline applies (almost) 
cleanly there, to 4.0 branch.

-- 
Eric Botcazou