We're trying to follow the pattern described in https://www.dartlang.org/tools/pub/package-layout.html

TBR=iansf@google.com

Review URL: https://codereview.chromium.org/1210173004.

R=abarth@chromium.org

Review URL: https://codereview.chromium.org/1218593002.

1) Merge input example into widgets example
2) Move single-file, non-fn examples into a "raw" directory
3) Rename stocks-fn and widgets-fn to stocks and widgets

R=ojan@chromium.org

Review URL: https://codereview.chromium.org/1005393006

Previously we would spend a lot of time during startup processing all 3k stocks
in the data set. This CL breaks the data up into 100 stock chunks and loads
them incrementally off the network. A future CL will switch to loading them on
demand.

R=ojan@chromium.org

Review URL: https://codereview.chromium.org/1038533002