add docs for fileset and its example
addressed PR comments; also added an example for specifying an additional property for the output format
fix literal includes
remove app-manager scripts
address comments; removed the use of Avro for explaining output format properties and used TextOutputFormat.SEPERATOR instead to be consistent with the FileSetExample
added more prose about input/output format and links to their javadoc
addressing jj's last comment
Merge branch 'release/2.6.0' into feature/fileset-doc
Merge branch 'feature/fileset-doc' into release/2.6.0