spark source code tag cscope building

* CSCOPE*

find `pwd` -name "*.xml" -o -name "*.md" -o -name "*.java" -o -name "*.js" -o -name "*.ini" -o -name "*.scala" -o -name "*.sbt" -o -name "*.py" > cscope.files

cscope -b -q -k

*ETAGS*

find `pwd` -name "*.xml" -o -name "*.md" -o -name "*.java" -o -name "*.js" -o -name "*.ini" -o -name "*.scala" -o -name "*.sbt" -o -name "*.py" -print | xargs etags -a