Added the Avro Output Plugin for PDI
 'New version of plugin metadata'
Merge pull request #184 from graimundo/master

- Corrected version entry that had two build_id elements
 'New version of plugin metadata'
Merge pull request #185 from cdeptula/avrooutputv1

Added the Avro Output Plugin for PDI
 'New version of plugin metadata'
Added 5.2 versions for the ctools
Update Plug-in entry

Change Pentaho compatibility version and screenshots URLs.
Merge branch 'Biserver' of https://github.com/SPECUSA/marketplace-metadata
Fixing img urls for Bootstrap Designer
 'New version of plugin metadata'
Change Plugin zip file location and remove images

Change Plugin zip file location and remove some images of plugin
Merge pull request #187 from SPECUSA/Biserver

Change Plugin zip file location and remove images
 'New version of plugin metadata'
 'New version of plugin metadata'
 'New version of plugin metadata'
- Added Category and Development Stage to PDI entries