clang-format: add configuration and attributes

.clang-format

@@ -0,0 +1,14 @@
+---
+# This configuration requires clang-format 3.8 or higher.
+BasedOnStyle: Mozilla
+AlignAfterOpenBracket: Align
+AlignOperands: false
+AlwaysBreakAfterReturnType: None
+AlwaysBreakAfterDefinitionReturnType: None
+BreakBeforeBraces: Allman
+ColumnLimit: 100
+Standard: Cpp11
+# This requires clang-format 4.0 (at least).
+#FixNamespaceComments: true
+ReflowComments: false
+...

.gitattributes

@@ -1,3 +1,11 @@
+# Attributes used for formatting.
+[attr]our-c-style   whitespace=tab-in-indent  format.clang-format
+
+*.cxx   our-c-style
+*.h     our-c-style
+*.hxx   our-c-style
+*.cu    our-c-style
+
 data/* filter=lfs diff=lfs merge=lfs -text
 /**/data/* filter=lfs diff=lfs merge=lfs -text