(TK-71/74) Improve Webrouting error messages

Improve error messages in the Webrouting service when
a specified service or endpoint does not appear in the
webrouting configuration and when the :web-router-service
section of the TK configuration is absent.
(TK-71/74) Change to IllegalArgumentException

Change the IllegalStateException thrown in the init function
of the webrouting service to an IllegalArgumentException.
(PE-3366) Add link to testutils docs

Add a link to the testutils docs in the README.
Merge pull request #78 from fpringvaldsen/TK-71/74

(TK-71/74) Improve Webrouting error messages
(TK-47) Modify endpoint data structure

Modify the list of endpoints to be a map. Now, since an
endpoint can have multiple handlers registered on it,
each key in the map is an endpoint, with its value being a
vector of all the handlers registered at that endpoint.
(TK-54) Fix multiple default servers error message

Fix multiple default servers error message to be something
readable.
Merge pull request #79 from fpringvaldsen/PE-3366-testutils-link

(PE-3366) Add link to testutils docs
Merge pull request #81 from fpringvaldsen/TK-54-default-server-error

(TK-54) Fix multiple default servers error message
Merge pull request #80 from fpringvaldsen/TK-47

(TK-47) Modify endpoint data structure
(WIP) Add access logging to jetty
(TK-81) Add docs and test for request logback

Add a test for the new request logback feature. Add docs
explaining how to use the new configuration option.
(TK-81) Move custom appender

Move custom appender so that Travis can load it.
(TK-81) Address PR comments

Add example logback config file to docs folder. Clean up some
import statements. Add a comment explaining why the thread
needs to be slept in the request logging test.
Merge pull request #82 from fpringvaldsen/TK-81-request-logback

(TK-81) Add docs and example to request logging feature
(TK-84) Don't double encode query strings

The Java URI class encodes the "query" parameter when using its
multi-parameter constructor. In proxy-servlet we are using getQueryString
to get the query string to pass into URI, which does not URL decode the
query string. This change decodes the query string before passing it into
the URI class, which will then go ahead and reencode it.
(TK-84) Change :refer to :as

Use :as instead of :refer to improve readability.
Merge pull request #85 from fpringvaldsen/TK-84_double_encoding

(TK-84) Don't double encode query strings