AllPlot - Smoothing also for "Left Border"

... data points of "Smoothing" setting were set to zero for the first "smoothing number" points
... this causes e.g. Zero Altitude Values when Plot Smoothing is active (see screen shot below)
... with the patch, also most left values are "smoothed" now 

(the algorithm used here for smoothing also works if the number of datapoints left/before the datapoint smoothed is smaller than "applysmooth" datapoints)

Here the status "before" the patch to illustrate the problem (noticed that for "Altitude" since the ride started above 1000 m and with smoothing active the Y-Axis scale set from 000 to maxHeight of the ride.)
![allplot_smoothing_old](https://cloud.githubusercontent.com/assets/7491731/4261294/020b7f3e-3b69-11e4-9ee7-bf51e5007a08.JPG)