Changing to absolute values - update layout var

Reading screen Width and Height. A function computes the screen width
for the Time series graph space  according to a factor. The result is
forced to be an integer (Math.round method applied). The rest of the
code was updated according to this
Headers without blank spaces

Because D3 does not like blank spaces while parsing. And to avoid over
coding each header that we want to parse. See in:
http://stackoverflow.com/questions/21715201/unable-to-reference-d3-js-data-imported-from-a-csv-file-with-spaces-in-the-heade