Found few initialization errors in admin.rb, will get the following errors using enable_all and disable_all from Shell.
hbase(main):019:0> disable_all 't1*'
ERROR: undefined local variable or method `admin' for #<Hbase::Admin:0x447fa959>
Did you mean? @admin
Drop_all table by regex fail from Shell - Similar to HBASE-23134
GitHub Pull Request #698