Font size of the whole app would ideally be controlled by a single
value. This value is currently hard coded using the :root CSS selector.
It is the intention to make this value configurable within riot. In the
interim all font-sizes have been converted to rem by the simple process
of regex. Replacing px values with their equivalent rem values assuming
a font size of 15px and then rounded to three decimal places, which was
the base at the time of this transformation.
I'm expecting another commit cleaning up rem values but I thought it
best to leave that to review.
This commit doesn't address any scaling issues. I thought it better to
land this unwieldy, mechanical, invisible change before the others
otherwise the pr would be impossible to review thoroughly.
