Delete unused catch clause.

* src/dctc/java/com/dataiku/dctc/Main.java: Here.
tail: Correct an catch clause.

* src/dctc/java/com/dataiku/dctc/command/Tail.java (performByte): Here.

* src/dctc/java/com/dataiku/dctc/command/Command.java: Add a method
  for error management.
Correct longOpt from the Command class.

* src/dctc/java/com/dataiku/dctc/command/Command.java: Right behavior
  for naming, set the argument name.
* src/dctc/java/com/dataiku/dctc/command/Dispatch.java,
  src/dctc/java/com/dataiku/dctc/command/Edit.java: Adjust.
tail: Correct the spelling of the option name and arguments and add
the short version.

* src/dctc/java/com/dataiku/dctc/command/Tail.java (setOptions): Here.
Command need to manage the exception.

reported by Clément Sténac.

* src/dctc/java/com/dataiku/dctc/command/Command.java: Don't throws.