Add a .gitattributes file to force consistent line endings in text files.

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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78102584

.gitattributes

@@ -0,0 +1,14 @@
+# Auto detect text files and perform LF normalization
+* text=auto
+
+# Known text files
+*.java text
+*.xml text
+*.yml text
+*.md text
+*.properties text
+*.sh text
+
+# Known binary files
+*.jar binary
+*.gif binary