command: Reset the exitCode when needed.

* src/dctc/java/com/dataiku/dctc/command/AddAccount.java,
  src/dctc/java/com/dataiku/dctc/command/Find.java,
  src/dctc/java/com/dataiku/dctc/command/Grep.java: Here.
clean: Delete useless comment.

* src/dctc/java/com/dataiku/dctc/command/AddAccount.java: And space
  clean.
command: Clean the prototype.

* src/dctc/java/com/dataiku/dctc/command/abs/Command.java: Usage scat
  the dctc, cmdname, and the prototype.
* src/dctc/java/com/dataiku/dctc/command/AddAccount.java,
  src/dctc/java/com/dataiku/dctc/command/Cat.java,
  src/dctc/java/com/dataiku/dctc/command/Cmp.java,
  src/dctc/java/com/dataiku/dctc/command/Cp.java,
  src/dctc/java/com/dataiku/dctc/command/Dispatch.java,
  src/dctc/java/com/dataiku/dctc/command/Edit.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/Head.java,
  src/dctc/java/com/dataiku/dctc/command/ListColumns.java,
  src/dctc/java/com/dataiku/dctc/command/Ls.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/Tail.java,
  src/dctc/java/com/dataiku/dctc/command/Version.java: The prototype
  does not contains the binary name and the command name.
Catch the current file for the error message.

* src/dctc/java/com/dataiku/dctc/command/Grep.java: And delete the
  fixme. Already done by the Command layer.
list-columns: Fix the long description.

* src/dctc/java/com/dataiku/dctc/command/ListColumns.java: Here.
list-columns: Managed compress content.

* src/dctc/java/com/dataiku/dctc/command/ListColumns.java: Call
  AutoGZip.
list-columns: Separator option.

* src/dctc/java/com/dataiku/dctc/command/ListColumns.java: -s,
  --separator with argument.
Update news feature.

* News.txt: Add list-columns command.
find: Manage the type.

* src/dctc/java/com/dataiku/dctc/command/Find.java: Print only
  directories, files or all with the option `-type'.
* News.txt: Update.
fix 80 columns.

* README.md: Needed for a readme.
packager: Make a distclean if needed.

* packager/create-dctc-selfextracting.sh: Here. Output to the standard
  error.
Ignore the packager output.

* .gitignore: Ignore package/dctc.
package: Avoid naming errors.

* packager/create-dctc-selfextracting.sh: Here.