add phony targets
do not clean files/directories automatically
remove useless comments/messages
use a timestamp to not run make install each time a win32 package is created

Signed-off-by: Rémi Denis-Courmont <remi@remlab.net>

LP#888002

Will help to 'undo' ASLR and make those reports useful

Same for sac3 Qclq and sqcp

http://forum.inmatrix.com/index.php?showtopic=6891 sac3
http://forum.videolan.org/viewtopic.php?f=7&t=80308 Qclq
http://discussions.apple.com/thread/750107?threadID=750107 sqcp

This allows specifying the libavcodec decoder/encoder by name
Useful in case there are more than one codec per fourcc

Example: ffvp8 / libvpx decoders for VP8

The VLC contrib patches for live555 are mandatory otherwise it will
not work correctly. Thus, linking directly from the live555 source tree
is not something that should be encouraged or even supported.

live555 should either be installed or built from contrib instead.

DLLs are named after their version (libvlc-5.dll) on wince

no sign of availability of real video DLLs for x86_64

fixes #5508