fix: Tail -c K.

* src/dctc/java/com/dataiku/dctc/command/cat/CatAlgorithmFactory.java:
  Here.
edit: Test earlier if we have file in the command line.

* src/dctc/java/com/dataiku/dctc/command/Edit.java: Before to test if
  the editor is set.
style: Update.

* src/dctc/java/com/dataiku/dctc/command/Edit.java: Here.
edit: Give the exception to the Command class.

* src/dctc/java/com/dataiku/dctc/command/Edit.java: Get the full stack
  trace if needed.
Clean the error messages.

* src/dctc/java/com/dataiku/dctc/command/Cmp.java,
  src/dctc/java/com/dataiku/dctc/command/Find.java,
  src/dctc/java/com/dataiku/dctc/command/Grep.java,
  src/dctc/java/com/dataiku/dctc/command/Mkdir.java,
  src/dctc/java/com/dataiku/dctc/command/Mv.java,
  src/dctc/java/com/dataiku/dctc/command/Rm.java,
  src/dctc/java/com/dataiku/dctc/command/Rmdir.java,
  src/dctc/java/com/dataiku/dctc/command/Sync.java,
  src/dctc/java/com/dataiku/dctc/command/abs/ListFilesCommand.java:
  Here.
Error management with a strategy design pattern.

* src/dctc/java/com/dataiku/dctc/command/policy/YellPolicyFactory.java:
  The factory.
* src/dctc/java/com/dataiku/dctc/command/policy/YellPolicy.java: The
  interface.
* src/dctc/java/com/dataiku/dctc/command/policy/QuashPolicy.java,
  src/dctc/java/com/dataiku/dctc/command/policy/SayYellPolicy.java,
  src/dctc/java/com/dataiku/dctc/command/policy/HowlPolicy.java: The
  implementation (silent, error - normal -, debug).
Use the new erro management.

* src/dctc/java/com/dataiku/dctc/command/abs/Command.java: Here.
Delete debug option in all commands.

* src/dctc/java/com/dataiku/dctc/command/abs/Command.java: Set the
  environment variable DCTC_DEBUG or DCTC_SILENT to affect the output
  style.