better looking icons

not perfect but better for now
better info management #18
swapped the little triangles to conform with our TOCs
some more cleanup for the info panel JS code
make download links clickable
auto cleanup
no need for manager reference

helper plugins have their own access to getConf/getLang
some doc cleanups
auto cleanup
comment cleanup
fallback is already done in handle()
return value was never used
more clarification access and types
auto cleanup
fixed comments and visibility
auto cleanup
some more comments
auto cleanup
Added missing error text, fixes #11
Added source repository link to details, fixes #28