clang-format: Always break template declarations

I find this format easier to read, because the definitions are at the
expected indentation, making it easier to find what I'm looking for.

src/displayapp/screens/Screen.h

@@ -10,7 +10,8 @@ namespace Pinetime {
 
     namespace Screens {
 
-      template <class T> class DirtyValue {
+      template <class T>
+      class DirtyValue {
       public:
         DirtyValue() = default; // Use NSDMI
 

src/displayapp/screens/ScreenList.h

@@ -12,7 +12,8 @@ namespace Pinetime {
 
       enum class ScreenListModes { UpDown, RightLeft, LongPress };
 
-      template <size_t N> class ScreenList : public Screen {
+      template <size_t N>
+      class ScreenList : public Screen {
       public:
         ScreenList(DisplayApp* app,
                    uint8_t initScreen,