Fixes #162 Installation issue (build failing)
Initial support for sequenced addons (#164)
Fixes #165 Generic system to extract attachment metadata upon upload
Fixes #166 Extract image dimensions upon upload and store them as metadata
Fixes #168 Support for CMYK JPEGs (and other exotic JPEG images)
Fixes #167 Performance issue when serving images
Leftover for #165 Generic system to extract attachment metadata upon
upload