added my homework.
Merge pull request #2 from xiuyanni/xiuyan

added my homework.
Update ex0.txt

just find that we submit a wrong version of our data. it is an updated version. Please discard the previous one.
created ex0_updated.txt
add syncing, quote escape and clone correction
"need to merge to update instructions"
Merge branch 'master' of github.com:cuny-ml-f2014/homework1
changed the fonts from verbatim to code and included quotes properly
corrected the last set of quotes.
corrected the placement of the clone box picture
added syncing upstream
Merge pull request #4 from xiuyanni/xiuyan

Update ex0.txt
Merge pull request #3 from xiuyanni/patch-1

created ex0_updated.txt
corrected headings
changed gitignore
added section to add upstream remote repository
Merge remote-tracking branch 'upstream/master'