Add support for substing template

As an uploader, I want to use a ingestion template and be able to
subst it, so that the config is stored on wiki and can make use of
parser functions.

Add to UploadBot constructor an additional parameter allowing
to set whether the template should be substed (recursively).
Fix bug with lack of extension for file upload

It seems that the extension must be specified when uploading the file.
As it is held in the metadata dictionary, this is actually no problem
to retrieve and append to the title.
Remove useless print statements
Add Processing method to split and apply a template.

As a developer, I want to transform a list of values to
be wrapped in a Commons template - such as Technique.

Add a general method which splits a string following a given
separator, translate each bit using a given dictionary, and wraps
each in a given template.
Add method implementing the above for {{Technique}}.