conf: make the parent path to create the configuration file.

* src/dctc/java/com/dataiku/dctc/configuration/Configuration.java: Here.
Clean the display when the bitrate is displayed. Closes #11.

Delete usage case when the shell create a new line.

* src/dctc/java/com/dataiku/dctc/display/AbstractThreadedDisplay.java,
  src/dctc/java/com/dataiku/dctc/display/AbstractTransferRateDisplay.java: Implementation.
* src/dctc/java/com/dataiku/dctc/display/LessSimpleDisplay.java,
  src/dctc/java/com/dataiku/dctc/display/SimpleDisplay.java: Usage cases.
Could display with the less simple format.

* src/dctc/java/com/dataiku/dctc/display/DisplayFactory.java: Named
  tty-pretty.
s3: Catch unable to unmarshall response. Closes #3.

* src/dctc/java/com/dataiku/dctc/file/S3File.java: Assume comes to
  directory/bucket cat.
cat: Better exception message.

* src/dctc/java/com/dataiku/dctc/command/Cat.java: Here.
log: Level of debug.

* src/dctc/java/com/dataiku/dctc/DCTCLog.java,
  src/dctc/java/com/dataiku/dctc/command/Command.java: Hide the stack
  trace in error level.