Handle non-atom method names

When a request contains a non-standard HTTP method name, Erlang and
mochiweb return it as a string rather than an atom. This caused problems in
several parts of webmachine, including logging and tracing.

Fix all parts of the code that assumed method names were always atoms. Add
new unit tests for the fixed areas.
Merge pull request #217 from basho/non-standard-method

Handle non-atom method names
Change reference to listening port to 8080

The template used by scripts/new_webmachine.sh (wmskel) sets the
listening port to 8080 (in priv/templates/src/wmskel.app.src), not 8000
(as is used in the demo app).
Merge pull request #218 from derek121/port-used-in-docs

Change reference to listening port to 8080

Reviewed-by: reiddraper
Add request timing option for access logger

Add the ability to specify a boolean configuration parameter to the
webmachine_access_log_handler module to have it include request
duration reporting as part of its log output. The request durations
are reported in microseconds and this option is disabled by default so
that the current default behavior is maintained.