added instructions for generating the gmsh files

gmsh/instructions.txt

@@ -0,0 +1,15 @@
+In order to generate the mesh files used in the thesis, use the following for
+values of 'a' in the .geo files:
+
+2D:
+1 0.04900     529 vertices    1060 elements
+2 0.01500    5083 vertices   10168 elements
+3 0.00490   50354 vertices  100710 elements
+4 0.00150  534608 vertices 1069218 elements
+
+
+3D:
+
+1 0.08850     1915 vertices     10635 elements
+2 0.01880   170297 vertices   1008870 elements
+3 0.00885  1701554 vertices  10188506 elements