Fixes symbol lookup errors when loading an addon module on Linux.

fixes #2465

Fixes #2388

Conflicts:
	src/udp_wrap.cc

SecureContext.setOptions() is backed by SSL_CTX_set_options() which, contrary to
what the name suggests, is additive: it doesn't set options, it adds them to the
already active options.

Hence the need for SecureContext.clearOptions(), which lets you unset active
options.

Creating a file event watcher with fs.watch({persistent:false}) should not block
the event loop.

Copies the POST request data verbatim into the response body.

Unfortunately valgrind must be used to see the bad read. It would be nice if
we could improve this test to cause a segfault.

Conflicts:
	src/platform_win32.cc

node::Loop() replaces the NODE_LOOP macro. This avoids hitting
v8::Isolate::GetCurrent() for each loop lookup when HAVE_ISOLATE==0

Require reorganizing the isolates somewhat.

Add a very simple test.