Slightly better error messages on failed startup
preparing for yaws 1.96
add documentation of exhtml directive to yaws.tex (by tjeerd)
Move WebDAV to an appmod, the locking server to a runmod (tjeerd)

All WebDAV functionality is moved to an appmod so the extension methods and
additional response headers are not part of yaws_server.erl and yaws.erl
anymore. Also the locking server is now a runmod so it is not started by
the supervisor and can be used only when needed.

Additionally the 100-Continue code is moved so it can be returned to all
requests that contain a body.

The WebDAV functionality is tested against the litmus test. All tests are
passed, except the ones that require unsupported properties. The test shows
this as a fail while returning 404 should be sufficient.
fix compiler warnings in Yaws applications
increase server stop wait time for tests

Increase the server stop wait time in test/support/include.mk.in so that
it's long enough to work with debug builds.
fix comment heads and some indentation in yaws_appmod_dav
fix dialyzer warnings
remove obsolete references to removed yaws_dav module
General whitespace and indent cleanup, removed trailing whitespace and constrained code to 80 cols
clean up & clarify code in yaws_api:setconf/3
add yaws_api:get_listen_port/1

For testing scenarios it can be useful to configure yaws to run on an
ephemeral port by setting the server port number to 0. Add the
yaws_api:get_listen_port/1 function to enable callers to retrieve the
actual port number of a server from its listen socket. The single argument
to the function is the #sconf{} record for the target server.
fix spelling error in sconf access function name
enhance yaws_api:get_listen_port/1 documentation