added --ignoreFailure flag to mkdir. mkdir would fail if the file exists, By specifying --ignoreFailure, don't have check if the folder already exists

added ls command. a easier way to test the API, and get information about a folder

added additional error cases.

updated README.md
instead of doing System.out, changed to use Logger.info
Merge branch 'develop' into feature/mkdir_ignoreFailure_and_ls

* develop:
  specified source encoding to suppress warning
Merge from develop
Merge pull request #6 from Roambi/feature/mkdir_ignoreFailure_and_ls

added --ignoreFailure flag to mkdir. mkdir would fail if the file exists...