First set of patches for the server plugin to work over USB

Tested with syncml-ds-tool and could see the exchange of syncml messages. This proves that the basic USB connectivity works. But sync fails and it could be because of the usage of QSocketNotifier or the syncml-ds-tool exiting pre-maturely. This needs to be checked further. This patch requires a change in Buteo::TransportTracker to enable USB transport in buteo-syncfw.

What all I did to make Sync over USB:
* Move usb_moded to some other binary name, say usb_moded.bkp
* In file /etc/modprobe.d/usb_moded.conf, have only one line "options g_nokia", remove the rest
* We will use syncml-ds-tool from libopensync project from PC
* No need of obexd since syncml-ds-tool does not care about capability file
* Copy the buteo binaries to device (n950) and make the necessary soft links
* The default image in n950 did not have libwbxml2, copy it from /srv/mer/targets/n950rootfs/usr/lib to the device /usr/lib
* msyncd has to be run as root, since opening /dev/ttyGS1 requires root privileges. This needs to be checked later, if a non-root process can open device node
* In the host, run the syncml-ds-tool like:
    sudo syncml-ds-tool -u 1 --identifier "PC Suite" --sync text/x-vcard Contacts
(sudo has to be used, since otherwise, the USB descriptor has to be added to udev list)

Most of the above steps are hacks (like disabling usb_moded etc.) that are expected to be fixed as we move forward