Fixes in config.php and update_plotly.py

config.php
=======
- Added option for Kelvin degrees.
- Removed odd whitespaces.
- Removed odd commas in arrays.

update_plotly.py
============
Changed parameter name "username" to "username_or_email" due to error:

      File "/var/www/PiTemp/update_plotly.py", line 18, in <module>
        update_temp(date,temp)
      File "/var/www/PiTemp/update_plotly.py", line 7, in update_temp
        py = plotly.plotly(username='LiborGabaj', key='wqardabr7c')
    TypeError: __init__() got an unexpected keyword argument 'username'