added plugins not backed up and postgresql addon link (#193)
added plugins not backed up and postgresql addon link (#193)

* added plugins not backed up and postgresql addon link

*  added addons directory path in not backed up section

gocd/docs.go.cd,gocd/docs.go.cd,ketan/docs.go.cd,gocd/docs.go.cd,ketan/docs.go.cd,ketan/docs.go.cd