Add Node.js SDK

Added Node.js SDK for PredictionIO by Asaf Yishai to Community-powered
Projects
Update movielens.md
MLlib classification template
Add C#/.NET SDK

Added C#/.NET SDK for PredictionIO by Themos Piperakis to
Community-powered Projects
PDIO-340 Remove EventID class. Use String for EventID.
Move temporary test code to examples
PDIO-342 Allow import events with predictionKey
Initial draft for Launching PredictionIO on AWS

Revised for 0.8, need to check security group settings
PDIO-342 Return predictionKey in predicted result
change entityType to pio_pr for shorter name
PDIO-342 Fix missing quote in predictionKey value. and
add predictionKey for itemrank's Prediction class
Add Vagrant Installation for PredictionIO

Added Vagrant Installation for PredictionIO by Raphael Mäder to
Community-powered Projects

Also added links from main Installation documentation
Rename and restructure MLlib ALS template
Return top n products
Rename Prediction to PredictedResult
PDIO-370
Merge branch 'develop' of https://github.com/PredictionIO/PredictionIO into develop
Rename Prediction to PredictedResult in hello world example
Remove obsolete example
Remove obsolete templates
PDIO-371 Rename EmptyActual to EmptyActualResult. Remove
EmptyQuery and EmptyPrediction helper class