Changed python invocation to use /usr/bin/env instead of /usr/bin/python.  Adding instrument_serial_connection.cxx and h. Changed automake stuff to use version compatible with MAC autoconf.
Incremental development; port_agent now tries to initialize instrument_serial_connection.  Need to flesh that out now.
Port agent working now with serial connection and configurable settings.
Turned off hard code single thread.
Fixed problem with removing publisher from list. Fixed probem with break parameter.  Close
serial device FD if one exists before opening.
Cleaned up initialization so that we don't have to close the port if
serial settings have changed.
If device path changes, reinitialize serial settings too.
Added error handling for when error occurs opening device file.
Attempt to fix memory leak.  Made error stringstream not be dynamically allocated, but rather a single class member that is reused.
Added setsockopt SO_REUSEADDR.
Merge pull request #1 from deverett/master

Serial Capability in Port Agent.