Added median approximation to data analysis, used for sonar outlier filtering.

controls/DataAnalysisTool/Tool/ApproxMedFilt.m

+function [ y ] = ApproxMedFilt( x, eta)
+%APPROXMEDFILT Summary of this function goes here
+%   Detailed explanation goes here
+mean = x(1);
+med = x(1);
+y = zeros(size(x));
+for i = 1:length(x)
+    mean = mean + (eta * (x(i) - mean));
+    med = med + (eta * sign(x(i) - med));
+    y(i) = med;
+end
+