Get ourselves some clang-format and apply it

Add clang-format and apply it to all *.cpp *.h files under jni/

Test: make
Change-Id: I3fe84eb3a65b73d8b38bb9bd52c07945835ede70
diff --git a/.clang-format b/.clang-format
new file mode 100644
index 0000000..9127163
--- /dev/null
+++ b/.clang-format
@@ -0,0 +1,12 @@
+BasedOnStyle: Google
+AccessModifierOffset: -2
+AllowShortFunctionsOnASingleLine: Inline
+ColumnLimit: 100
+CommentPragmas: NOLINT:.*
+DerivePointerAlignment: false
+IndentWidth: 4
+ContinuationIndentWidth: 8
+PointerAlignment: Left
+TabWidth: 4
+UseTab: Never
+PenaltyExcessCharacter: 32