fix: Delete error message.

* src/dctc/java/com/dataiku/dctc/configuration/GlobalConf.java: Here.
Delete unused method.

* src/dctc/java/com/dataiku/dctc/command/Ls.java: Delete new_line.
Correct portability with FreeBsd.

* packager/create-dctc-selfextracting.sh: wc insert spaces before the
  number.
ssh: Correct path when no colon is given.

* src/dctc/java/com/dataiku/dctc/file/SshFileBuilder.java: Keep the
  host as the host.
ssh: Display the cause of the exception.

* src/dctc/java/com/dataiku/dctc/file/SshFile.java: Given the message
  and keep only the message, and not the libray error location.
Delete useless failed message.

* src/dctc/java/com/dataiku/dctc/command/Command.java: Don't this
  `failed' in the message.
Don't display the null value

Closes #58.

* src/dctc/java/com/dataiku/dctc/command/Tail.java: Here.
tail: Fix the underflow.

Closes #13.

* src/dctc/java/com/dataiku/dctc/command/Tail.java: Add a floor.
ftp: Check the port even if be contained in the configuration file.

Clean in the same time the message error.
Closes #1.

* src/dctc/java/com/dataiku/dctc/file/FTPFileBuilder.java: And
  refactor some.