Add continuum mechanics' P4 lab session

Change-Id: I15a80d28235451f82743b553044662dd66876764
diff --git a/quad8/continuummechanics/lab/p4/data/regresio.dat b/quad8/continuummechanics/lab/p4/data/regresio.dat
new file mode 100644
index 0000000..70781da
--- /dev/null
+++ b/quad8/continuummechanics/lab/p4/data/regresio.dat
@@ -0,0 +1,10 @@
+0.6	0.55495
+0.5652173913	0.54695
+0.5238095238	0.501
+0.4736842105	0.4008
+0.4117647059	0.38045
+0.3333333333	0.33385
+0.2857142857	0.2607
+0.2307692308	0.20705
+0.1666666667	0.17075
+0.09090909091	0.09875