add empty demo1 template
Merge branch 'production' into demo1
Merge branch 'master' into demo1
Merge branch 'master' into demo1_shumo

Conflicts:
	appengine/myria_web_main.py
make graph.js work without profiling chart.
fake example.
fix the problem of still using chartElement at
some places.
change the bottom to selection list style.
let query plan viz support NAryOperator.
make `queryPlan` as a class variable rather using 
the global variable `queryPlan`. since in a page 
there could be two query plans now.
add logic of switching query plan in demo.js.
Fix a small bug in visualization.
compile plan after clicking button.
make the animation faster.
Move D3 init out of queryvis.js. 
Fix issues in by the comments.
refactor plan generation.
Fix typos, correct indentation
Merge pull request #57 from uwescience/demo1_shumo

demo1 part 1