New design of Workbench welcome page.
Welcome page: Changed 'download it now' button to Google Play and App Store buttons.
Removed evothings-app.css because it will be copied from the EvoThingsExamples repo by the EvoThingsStudio build script. It was also added to .gitignore so that a copy of- or symlink to EvoThingsExamples evothings-app.css can be put here for e.g. development purposes.
Welcome page: Added 'Manual download' button that leads to evothings.com/download/#otherdownloads.