Cleaned up and added TiDB Server info (#1076)
Cleaned up and added TiDB Server info (#1076)

* Cleaned up and added TiDB Server info

* More doc cleanup

* Fixed table of node mappings

* Clarified command line parameters

* Fixed letter casing and indenting

* Clarified need to download binlogctl

pingcap/docs,pingcap/docs,pingcap/docs