make all tests and ebos compile when selecting float or quad as Scalar

at least, they compile as far as eWoms is concerned. Some external
libraries (in particular everything which uses SuperLU) still have
issues.

Also, there seem to be issues with the precision that is achievable
by the Newton method when using float.

examples/problems/lensproblem.hh

@@ -403,7 +403,8 @@ public:
 
         if (onLeftBoundary_(pos) || onRightBoundary_(pos)) {
             // free flow boundary
-            Scalar densityW = WettingPhase::density(temperature_, /*pressure=*/1e5);
+            Scalar densityW = WettingPhase::density(temperature_,
+                                                     /*pressure=*/Scalar(1e5));
 
             Scalar T = temperature(context, spaceIdx, timeIdx);
             Scalar pw, Sw;