March product improvements

Our engineering team is hard at work on a big project that we look forward to showing off. But in the meantime, we also took care of a few miscellaneous product improvements in March.
- On the Opportunities page, "won" and "lost" opportunities now are shown as having a 100% and 0% confidence estimates, respectively, which means that they affect "Expected Value" in a more sensical way. Previously if you wanted this behavior you had to both mark an opportunity with a "won" status as well as manually updating the confidence of the deal. Now, you can simply mark the deal as "won".
- Since we now offer manual call logging, call-related stats have been exposed to Basic users in the Activity Report.
- Fixed a bug where the "status" column would show an outdated information after a certain status was deleted and replaced with another status.
- Explorer: Fixed a bug where drilling into multiple layers of a bar chart would throw an error.
- Explorer: Fixed a bug where the PNG image export option wasn't working.
- Improved the API by making the "type" field optional for contact's email addresses and phone numbers
- Fixed Importer's errors related to certain file encodings and custom fields containing dots
- Exporter: Significantly sped up long exports (up to 5x performance boost) and introduced a parameter that lets the API users automate exports w/o getting a confirmation email every time they are done.
And finally, an inspirational sales message while the app is loading!
