text: Title: Alluxio documentation defects
  Body: **Summary**
  
  This pinned issue is a running list of all documentation defects. If you find any defects or have any suggestions to our documentation site (https://docs.alluxio.io), you can also post under this issue.
  
  Maintainers will periodically clean up issues listed here.
  
  ## TODO
  
  ### priority-high (Something missing, misleading or incorrect, plus critical content)
  
  * Talk about server-side encryption for S3 bucket, e.g. when to set `alluxio.underfs.s3.secure.http.enabled` and `alluxio.underfs.s3.server.side.encryption.enabled` and `alluxio.underfs.s3.endpoint`
  
  * Improve [S3 API page](https://docs.alluxio.io/os/user/stable/en/api/S3-API.html#rest-api), there is no introduction on the setup of "EXAMPLE USAGE". e.g., for command `curl -i -X PUT http://localhost:39999/api/v1/s3/testbucket`, what is `testbucket`? it is used without any introduction.
  
  * Explanation on Some commands in [fsadmin page](https://docs.alluxio.io/os/user/stable/en/operation/Admin-CLI.html#report) is too brief, e.g., `fsadmin report storage` has only one line to explain
  
  * Not all the Alluxio shell fs commands are covered in page https://docs.alluxio.io/os/user/stable/en/basic/Command-Line-Interface.html, including `distributedLoad` and etc
  
  * Add Quick-Get-started: Running Presto with Alluxio on S3
  
  * Add Quick-Get-started: Running Spark with Alluxio on S3
  
  * Update [Use-Cases.html](https://docs.alluxio.io/os/user/stable/en/Use-Cases.html) which needs to be aligned with updated message from Alluxio website
  
  * Revisit deploy docs, especially Local, Cluster, Docker, K8S to be more consistent and user-oriented
  
  * Add Glue related instructions to EMR integration documentation 
  
  * Pros/Cons on EMR bootstrap vs YARN integration
  
  * Add Impersonation Configure for YARN and Spark page (e.g., Spark on YARN). [link at Slack]( https://alluxio-community.slack.com/archives/CEXGGUBDK/p1565067985154500)
  
  * Improvement in the "journal management" document: e.g., it is not clear a secondary master can not start with embedded journal ([link at Slack](https://alluxio-community.slack.com/archives/CEXGGUBDK/p1565270507214800?thread_ts=1565216871.196800&cid=CEXGGUBDK)); e.g., manually trigger checkpoints with the checkpoint command (`bin/alluxio fsadmin checkpoint`)
  
  ### priority-medium (changes will dramatically improve the docs)
  
  * Improve  [FS API](https://docs.alluxio.io/os/user/edge/en/api/FS-API.html), e.g. More explanation and examples in this page.
  
  * Improve or split [Namespace-Management.html](https://docs.alluxio.io/os/user/stable/en/advanced/Namespace-Management.html). This page is not well structured and currently too long to read.
  
  * Improve or split [Alluxio-Storage-Management.html](https://docs.alluxio.io/os/user/stable/en/advanced/Alluxio-Storage-Management.html). This page is not well structured and currently too long to read.
  
  * More detailed documentation  about `generate-tarball` script
  
  * More detailed instructions or examples in instructing how to connect to Kerberized HDFS as UFS
  
  * Add link to Spark performance tuning tips to [Spark page](https://docs.alluxio.io/os/user/stable/en/compute/Spark.html)
  
  ### priority-low (changes good to have)
  
  * Add "How Alluxio Works page", either restructuring the Architecture and Data Flow page or having a new ([link at Slack](https://alluxio-community.slack.com/archives/CEXGGUBDK/p1565396266284600?thread_ts=1565358306.250300&cid=CEXGGUBDK))
  
  ## DONE
  