(TK-44) Add webrouting docs

Add docs explaining how to use and configure the webrouting
service.
Ensure :default route-id specified

Using schema, ensure that a :default route-id is specified when
specifying multiple web-routes.
(TK-44) Add webrouting example

Add a webrouting example app to the documentation.
(TK-44) Add link to webrouting docs in README

Add a link to the webrouting docs in the main README file to make
it easy to find.
(TK-44) Add info about intent of Webrouting Service

Add information about the intent of the Webrouting Service to the
beginning of the webrouting-service.md file.
(TK-44) Improve wording in Webrouting description

Improve the wording of the description of the Webrouting Service
in the main README file.
Remove unused def

Remove a def that was never used anywhere in the code.
Merge pull request #46 from fpringvaldsen/TK-44-webrouting-docs

(TK-44) Webrouting Documentation