Create driver throws exception on open() about turtlebot_create

[PaulBouchier]

Problem understood.

From http://sourceforge.net/p/pyserial/code/HEAD/tree/tags/release2_7/CHANGES.txt:

Version 2.6 2011-11-02

Bugfixes:

• [Bug 3093882] calling open() on an already open port now raises an exception

On Ubuntu 14.04:
less /usr/lib/python2.7/less /usr/lib/python2.7/dist-packages/serial/init.py shows:
VERSION = '2.6'

On the working Ubuntu 12.04 system, the same command shows VERSION = '2.5'

The actual code which throws the exception is in serialposix.py:
def open(self):
"""Open port with current settings. This may throw a SerialException
if the port cannot be opened."""
if self._port is None:
raise SerialException("Port must be configured before it can be used.")
if self._isOpen:
raise SerialException("Port is already open.")

I confirmed by opening a port in python manually that it does throw that exception.

So the root cause is the API changed between pySerial 2.5 used on Ubuntu 12.04 and pySerial 2.6 used on Ubuntu 14.04. The solution is the open() statement has to be removed in Indigo. I'll submit a pull request for the github official turtlebot repo in a little while, which will fix some other breaks in the turtlebot build, but someone should fix the yujinrobot repo.

[kentsommer]

Fixed with this merge: #18