chore(gradle.properties): Remove gradle.properties file.

Not needed anymore with switch to using a combination of package.json
and Gruntfile.
fix(fineuploader.css): Remove extra header

Since header is appended via the Gruntfile, there is no need
to have a header here.
docs(overview/index.html): Show current version from package.json

docfu now injects all the package.json variables into each template
for possible use. Take advantage of this and show the version
in the source code examples.
docs(docs/overview/development.html): fix SauceLabs badge
docs(README.md): remove redundant text, cleanup
docs(README.md): typo
Merge branch 'develop' of github.com:Widen/fine-uploader into develop