Add clang-format file

.clang-format

+---
+Language: Cpp
+BasedOnStyle: LLVM
+SortIncludes: true
+AccessModifierOffset: -4
+AlignConsecutiveAssignments: false
+AlignConsecutiveDeclarations: false
+AllowShortIfStatementsOnASingleLine: false
+AllowShortFunctionsOnASingleLine: Inline
+BinPackParameters: false
+BinPackArguments: false
+ColumnLimit: 125
+ConstructorInitializerAllOnOneLineOrOnePerLine: false
+DerivePointerAlignment: false
+ExperimentalAutoDetectBinPacking: false
+IncludeCategories:
+  - Regex:           '^<.*'
+    Priority:        1
+  - Regex:           '^<.*\.h*>'
+    Priority:        2
+  - Regex:           '.*'
+    Priority:        3
+IncludeIsMainRegex: '([-_](test|unittest))?$'
+IndentCaseLabels: false
+NamespaceIndentation: All
+PointerAlignment: Left
+SpaceBeforeParens: Never
+Cpp11BracedListStyle: true
+Standard: Cpp11
+IndentWidth: 4
+TabWidth: 4
+UseTab: Never
+ContinuationIndentWidth: 4
+...