Merge branch 'ampcamp4' of github.com:amplab/training into ampcamp4
Merge branch 'ampcamp4' of github.com:amplab/training into ampcamp4
Merge pull request #130 from jegonzal/graphx-tutorial

Graphx tutorial
Many small changes to make things consistent for AMP Camp 4.
Updating Spark binary path
Bug fix for blinkdb
Merge branch 'ampcamp4' of github.com:amplab/training into ampcamp4
add solution code section and minor updates
Merge pull request #131 from mengxr/ampcamp4

 Add solution code section and minor updates
Minor revisions
making hint code blocks editable and fixing subgraph exercise
typo