Merge pull request #65 from nguyenxuanluong-luvina/master

Fix bug #438 , #439
Fix bug cannot get error information for OS Job
Merge pull request #67 from nguyenvannghia-luvina/master

Fix bug cannot get error information for OS Job
Update chart of job MySQL.Performance.MyISAMKeyBuffer
Fix bug interval = 0
Merge pull request #68 from maixuanthanh-luvina/master

Update chart of job MySQL.Performance.MyISAMKeyBuffer
Merge pull request #69 from nguyenvannghia-luvina/master

Fix bug interval = 0
Update installer.groovy for WiperdogServiceInstallation screen