---------------------------------------------------------------
git filter-branch --index-filter \
- 'git ls-files -s | sed "s-\t-&newsubdir/-" |
+ 'git ls-files -s | sed "s-\t\"*-&newsubdir/-" |
GIT_INDEX_FILE=$GIT_INDEX_FILE.new \
git update-index --index-info &&
mv $GIT_INDEX_FILE.new $GIT_INDEX_FILE' HEAD