Exclude generated class files from git

Summary: These get generated by VSCode if you have java installed and open the flipper project.

Reviewed By: danielbuechele

Differential Revision: D16763411

fbshipit-source-id: 40c7d943ee2ee32cf70f9aea080f5e44716e5651

.gitignore

@@ -21,6 +21,8 @@ local.properties
 .project
 .settings
 **/.classpath
+android/*/bin/**/*.class
+libs/*/bin/**/*.class
 
 # Mac OS X
 *.DS_Store