Adding connectedLimit option, for specifying the number of consecutive None values to draw over when in connected line mode.
Adding support for an optional limit parameter to keepLastValue() which lets the user connect line segments with gaps of less than N datapoints.
Fixing a bug in the connected lineMode where a line would falsely be drawn from the top left of the graph area to the first datapoint.
Merge pull request #118 from hostedgraphite/master