DOC: example notebooks use deprecated yahoo API (quantopian#285)

The NBs now uses google API

Revert "Removed group_adjust/group_neutral flag from information anal…

…ysis API"

This reverts commit 2eed755.

The original commit was a mistake as the IC is computed both on the full
factor and by sector, so the flags don't change the IC at sector level but
they are still needed when computed the IC for the full factor

Updated example NBs with new API and improved price DataFrame explana…

…tion

Update version to 0.1.2

Update version to 0.1.1

Add stable release 0.1