(first version, tests passing - https://nexedi.erp5.net/test_result_module/20171220-64958276/16)

Summary:
This is a new business template for corporate identity documents - currently:

1. Slide(show)
2. Leaflet (aka two-pager)
3. Letter
4. Book (aka text document/sale offer/project report)

Details:
It adds templates and dialogs and can convert web pages (and event-letters) to html and pdf using wkhtmltopdf/cloudooo. The bt5 uses a default theme, which you can override to change the look. All templates are built the same way, so adding custom templates should be straightforward. The included tests compare rendered html & pdf to a predefined set of documents, which you can update automatically after changing the layout of template.

Noteworthy:

• book adds support to embed documents (the previous book functionality in run-my-doc)
• book adds support for embedding reports via url (eg project_module/123?report=Project_myReportName&key=value...)
• there is another bt5 "nexedi-corporate-identity" which adds software themes and reports we are using (requirement coverage, cost effort, etc) - our customization of the generic theme.

Faq:

1. why do you compare bmp images? => working version from Tristan, tried to do the equivalent with png, takes too much time (sorry Jerome)
2. why do you parse HTML with re (parse strings)? => worked on prod & everyone recommends beautifulsoup, but it's not available in erp5 and there is no "how to add x to erp5"

Feedback:
It's my first "real" commit to erp5 and I tried to follow the guidelines I'm maintaining but I'm sure there is plenty to correct... Please let me know so I can fix.