"Navigation" release of obsurvey

I've just released a new version of obsurvey.

You can now navigate around the survey editor with the arrow keys. This is what you expect to be able to do, because of the way obsurvey works. Now you can. You can also delete empty questions and options with backspace.

Surveys should load faster. Especially multipage surveys load almost instantaneously when jumping to next page.

There are many minor changes in this release also, and a few bugfixes as well.

I've decided to name larger releases of obsurvey. This release is named the "Navigation" release.

I know I promised the next release of obsurvey would include the possibility of embedding surveys in a webpage or blog, this release is a step on the way to that. The next release will include embed functionality.