[options] changed font to the font used in help
[options][help] moved background down a bit
[options][help] small layout tweaks
[options] fixed manifest/source urls in options
fixes #16
paves the way for #11 to get easy access to the urls
[options][help] small layout tweaks
[options] moved 'Add manifest' button
fixes #17
[options] show feedback when adding a manifest
fixes #18
[options] fix #15 - show link in error
merge version-0.3
[release] v0.3.3