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

internal/ceres/compressed_col_sparse_matrix_utils.h

@@ -32,6 +32,7 @@
 #define CERES_INTERNAL_COMPRESSED_COL_SPARSE_MATRIX_UTILS_H_
 
 #include <vector>
+
 #include "ceres/internal/port.h"
 
 namespace ceres {
@@ -58,10 +59,9 @@ void CompressedColumnScalarMatrixToBlockMatrix(
 // Given a set of blocks and a permutation of these blocks, compute
 // the corresponding "scalar" ordering, where the scalar ordering of
 // size sum(blocks).
-void BlockOrderingToScalarOrdering(
-    const std::vector<int>& blocks,
-    const std::vector<int>& block_ordering,
-    std::vector<int>* scalar_ordering);
+void BlockOrderingToScalarOrdering(const std::vector<int>& blocks,
+                                   const std::vector<int>& block_ordering,
+                                   std::vector<int>* scalar_ordering);
 
 // Solve the linear system
 //
@@ -101,7 +101,7 @@ void SolveUpperTriangularTransposeInPlace(IntegerType num_cols,
       const double v = values[idx];
       rhs_and_solution[c] -= v * rhs_and_solution[r];
     }
-    rhs_and_solution[c] =  rhs_and_solution[c] / values[cols[c + 1] - 1];
+    rhs_and_solution[c] = rhs_and_solution[c] / values[cols[c + 1] - 1];
   }
 }
 
@@ -132,7 +132,7 @@ void SolveRTRWithSparseRHS(IntegerType num_cols,
       const double v = values[idx];
       solution[c] -= v * solution[r];
     }
-    solution[c] =  solution[c] / values[cols[c + 1] - 1];
+    solution[c] = solution[c] / values[cols[c + 1] - 1];
   }
 
   SolveUpperTriangularInPlace(num_cols, rows, cols, values, solution);