style: Spaces, clean.
ssh: Drop default_path management.

* src/dctc/java/com/dataiku/dctc/file/SshFileBuilder.java: Here.
clean: Don't check if Params::getParam return a null value

* src/dctc/java/com/dataiku/dctc/file/ProtocolFileBuilder.java: Here.
Renaming: accountData -> accountSettings, protocolData -> rawPath.

* src/dctc/java/com/dataiku/dctc/file/GSFileBuilder.java,
  src/dctc/java/com/dataiku/dctc/file/HDFSFileBuilder.java,
  src/dctc/java/com/dataiku/dctc/file/LocalFileBuilder.java,
  src/dctc/java/com/dataiku/dctc/file/S3FileBuilder.java,
  src/dctc/java/com/dataiku/dctc/file/SshFileBuilder.java,
  src/dctc/java/com/dataiku/dctc/file/FTPFileBuilder.java: Here.
renaming: HDFS -> Hdfs.

* src/dctc/java/com/dataiku/dctc/file/HDFSFileBuilder.java: From here...
* src/dctc/java/com/dataiku/dctc/file/HdfsFileBuilder.java: ...to here.
* src/dctc/java/com/dataiku/dctc/file/HdfsFileBuilder.java: Adjust.
Add getParamOrEmpty to Params class.

* src/core/java/com/dataiku/dip/utils/Params.java: Here.
clean: Use when Params::getParamOrEmpty.

* src/dctc/java/com/dataiku/dctc/file/ProtocolFileBuilder.java: Here.
clean: String::isEmpty is more readable as String::length == 0

* src/dctc/java/com/dataiku/dctc/file/ProtocolFileBuilder.java: And
  could be faster.
Clean dctc protocol.

* src/dctc/java/com/dataiku/dctc/Main.java: Here.
Extend self packaging script for dctc.

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