Update README.rst

[ljimenezsidoo]

Use more than one color condition in a line

[elicoidal]

Suggestion (yours is fine too):

* If you want to use more than one color, you can split the attributes using ';':

.. code::
 
   options='{"fg_color": "red:red_color == True; green:green_color == True"}'

Example:

.. code:: xml

   ...
    <field name="arch" type="xml">
        <tree string="View name">
            ...
            <field name="name" options='{"fg_color": "red:red_color == True; green:green_color == True"}'/>
            ...
        </tree>
    </field>
    ...

[simahawk]

LGTM but please include module name in the commit. tnx :)