Concatenate all definitions of the method functions into one
instance of the function:

	sub vcl_pipe {
		foo;
	}

	sub vcl_pipe {
		bar;
	}

is now the same as

	sub vcl_pipe {
		foo;
		bar;
	}

This avoids all the magic related to the default functions and
hopefully makes the newly introduced "include" facility much more
useful.



git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@1284 d4fa192b-c00b-0410-8231-f00ffab90ce4