Modified document index page.
Fixed documents for defining sandbox module dependency to pom.xml
[WIP] Add document for CDH4 deployment.
Modified license year.
Modified parent pom for updating maven plugin and dependency version.
Modified documents for CDH4
Merge branch 'doc-cdh4' into 0.5-develop
Merge branch 'doc-license-year' into 0.5-develop
Fixed document bugs.