Add build script in OVSDB resources

Add build script in OVSDB resources

The script in this commit simplifies the build process of the OVSDB
project.
usage: ovsdb-build [-h] [-r] [-b] [-of13] [-v] [-g CHANGE_ID] [-start]
[-stop]
                   [-d DIRECTORY] [-t]
optional arguments:
  -h, --help            show this help message and exit
  -r, --reclone         Reclone the Controller/OVSDB repos
  -b, --rebuild         Build the Controller Project
  -of13, --openflow13   Enable OpenFlow 1.3 Support
  -v, --verbose         Verbose output
  -g CHANGE_ID, --gerrit CHANGE_ID
                        Gerrit Change ID
  -start, --start       Start the controller
  -stop, --stop         Stop the controller
  -d DIRECTORY, --directory DIRECTORY
                        directory
  -t, --tmux            Create tmux session

On first run it is recommended to run the following:

./ovsdb-build -r -b -start

You can add the `-d` option to specify the directory you want to build
in:

./ovsdb-build -r -b -d /home/dave/dev/opendaylight -start

This will clone the controller and ovsdb projects, build them, move the
ovsdb artifacts in to the controller directory and start the controller.

Gerrit Changes can be built and loaded to the controller with a single
command:

./ovsbd-build -g 5716 -start

The controller is started in the background. To access the OSGi ole
you can manually `telnet 127.0.0.1 2400` or you can add `-t` to let
the build script create a tmux session for you.

Change-Id: Ie98942843a90193a38e17e4a8cd09b2806942e5c
Signed-off-by: Dave Tucker <dave.j.tucker@hp.com>