fix formatting for (non-generated) internal source files

- Change formatting standard to Cpp11. Main difference is not having
  the space between two closing >> for nested templates. We don't
  choose c++14, because older versions of clang-format (version 9
  and earlier) don't know this value yet, and it doesn't make a
  difference in the formatting.
- Apply clang-format to all (non generated) internal source files.
- Manually fix some code sections (clang-format on/off) and c-strings
- Exclude some embedded external files with very different formatting
  (gtest/gmock)
- Add script to format all source files

Change-Id: Ic6cea41575ad6e37c9e136dbce176b0d505dc44d
diff --git a/internal/ceres/parameter_dims_test.cc b/internal/ceres/parameter_dims_test.cc
index c832260..ee3be8f 100644
--- a/internal/ceres/parameter_dims_test.cc
+++ b/internal/ceres/parameter_dims_test.cc
@@ -25,6 +25,7 @@
 #include "ceres/internal/parameter_dims.h"
 
 #include <gtest/gtest.h>
+
 #include <type_traits>
 #include <utility>
 
@@ -35,15 +36,15 @@
 static_assert(IsValidParameterDimensionSequence(std::integer_sequence<int>()) ==
                   true,
               "Unit test of is valid parameter dimension sequence failed.");
-static_assert(
-    IsValidParameterDimensionSequence(std::integer_sequence<int, 2, 1>()) == true,
-    "Unit test of is valid parameter dimension sequence failed.");
-static_assert(
-    IsValidParameterDimensionSequence(std::integer_sequence<int, 0, 1>()) == false,
-    "Unit test of is valid parameter dimension sequence failed.");
-static_assert(
-    IsValidParameterDimensionSequence(std::integer_sequence<int, 3, 0>()) == false,
-    "Unit test of is valid parameter dimension sequence failed.");
+static_assert(IsValidParameterDimensionSequence(
+                  std::integer_sequence<int, 2, 1>()) == true,
+              "Unit test of is valid parameter dimension sequence failed.");
+static_assert(IsValidParameterDimensionSequence(
+                  std::integer_sequence<int, 0, 1>()) == false,
+              "Unit test of is valid parameter dimension sequence failed.");
+static_assert(IsValidParameterDimensionSequence(
+                  std::integer_sequence<int, 3, 0>()) == false,
+              "Unit test of is valid parameter dimension sequence failed.");
 
 // Static parameter dims unit test
 static_assert(