makepack Code

Now cleaning build directories if CLEAN_BUILD is set.

The Makefile should now be able to handle both configure scripts and
Makefile.PL, however Makefile.PL is still untested.

Removed CLEANUP_METHOD which didn't work and added DOINST_SH_COMMAND.

Trying to add a method to adjust the contents of a package. Unfortunately
the CLEANUP_METHOD isn't really usable as it lacks root permissions.

Added rule for qemu and implemented DOWNLOAD_METHOD and UNPACK_METHOD.

It is now possible to name the revision and to optimize for pentium4

Prepared C optimizing flags and extra flags for checkinstall.

Added ms-sys rule. However, ms-sys doesn't honor the PREFIX environment
variable.

Fixed typo

Some better presentation of BUILD_METHOD and INSTALL_METHOD