Enhance SelfUpdateCommand

* used %command.name% in help
* stop execution if phar is the same. And output a proper message
* do not ouput a fail message, then a success message if the phar is not
  valid
feature #250 Enhance SelfUpdateCommand (lyrixx)

This PR was merged into the master branch.

Discussion
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Enhance SelfUpdateCommand

* used %command.name% in help
* stop execution if phar is the same. And output a proper message
* do not ouput a fail message, then a success message if the phar is not
 valid

Commits
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5c39e5b Enhance SelfUpdateCommand
fixed typoe (closes #249)