Add release target, which is the same as release-custom.
[FEATURE] Create release notes from commit logs

* newBuildSystem/prepare-release-notes.py: Creates release notes
  from git log using the current tag and HEAD or any specific
  from..to tag.
  The release notes are only to be considered as a guide line
  of what has changed from one version to the other
* newBuildSystem/core.sh: Added name to print-config
* newBuildSystem/Makefile.default: Added target release-notes version=<version>
  in order to make it easy to create release notes via make
* python/clitools/__init__.py: Added some utility methods
  - run: run a command in bash. silent error output if required
  - run_or_error: run a command or bailout with an error if the command failed.
  - tool_config: parse the tools configuration
  - editor: determine a default editor to open to edit files
  - open_in_editor: launch an editor with the given file.
[FEATURE] Abort upload if the file already exists.
[FEATURE] Send an email on successfuly deploy.
[FEATURE] Add support for pre-releases.