fix Flattr buttons
Link to Airplay blog post

Add link to "Adding Airplay to a Sonos with Raspberry Pi" blog post
link to socos PyPI page
add more related projects
Address to github organization members has changed to /orgs/{orgName}/people
Merge pull request #1 from petteraas/fix_members_link

Address to github organization members has changed to /orgs/{orgName}/people