OSF API integrated + survey module reworked

v0.9.0.

improvements to testing

• when the test button is clicked in the edit run view, test emails are sent to your admin email address, not mailinator
• there are new buttons when testing surveys: a light bulb shows items that were hidden on the page, a magnifying glass shows debugging info (item names, requests sent to openCPU)
• our openCPU debugger (the accordion with info on the openCPU request) is now shown whenever there is an r problem (or you click the magnifying glass). it has the option to download the r code or the rmarkdown. That way you can edit it in Rstudio, which has much better code highlighting for debugging.

improvements to the survey module

• now hidden items work consistently: every showif is only called once unless the return value in R is NA.
• only items on the currently visible page are evaluated (before this calculate items at the end of the survey were also evaluated)
• we've minimised costly openCPU requests

css improvements

• there are no more flashes of unstyled content (where the mc_buttons only appear after a moment)

Open Science Framework API connection

• barring unforeseen changes on the side of osf.io it is now possible to connect runs to an OSF project. Currently, you can only export the Run-JSON there (in essence, saving all of the run structure and survey items). You can use this for pre-registration or version tracking.