Defined line as variable

Failed to run if local variable line is not defined
Corrected new arrays and strings

Using Array.new and String.new
Removed whitespace
Disable Rubocop Useless Assignment
Improved on the syntax
Improved on the syntax

Removed unneccesary string and improved how the commands are run
Merge pull request #678 from Claws-/master

Improved on the Ruby syntax
Update mysql-alive.rb

bug fix, db_pass should be config[:password].
Merge pull request #679 from mlf4aiur/patch-1

Update mysql-alive.rb
Update mysql-replication-status.rb

Added a socket argument
Merge pull request #680 from mlf4aiur/patch-2

Update mysql-replication-status.rb