Fix the following two warnings:

  src/unix/core.c:74:1: warning: ISO C90 forbids array
  'static_assert_failed' whose size can't be evaluated [-Wvla]
  src/unix/core.c:76:1: warning: ISO C90 forbids array
  'static_assert_failed' whose size can't be evaluated [-Wvla]

RSS is a reflection of the number of pages that a process has mapped.
glibc implements fopen() in terms of mmap() which means that trying
to read the number of mapped pages changes it. Switch to open().

Changes since version 0.10.4:

* unix: silence STATIC_ASSERT compiler warnings (Ben Noordhuis)

* windows: make timers handle large timeouts (Miroslav Bajtoš)

* windows: remove superfluous assert statement (Bert Belder)

* unix: silence STATIC_ASSERT compiler warnings (Ben Noordhuis)

* linux: don't use fopen() in uv_resident_set_memory() (Ben Noordhuis)

After latest twiddling, `stream->io_watcher.fd` doesn't contain a real
stream's file descriptior anymore. The one from `select_state` should be
used instead.

Zero-initialize `select_state->event` field.

The Makefile already did and now the gyp build does too. Fixes the
OpenBSD build of node.js.

Fixes nodejs/node-v0.x-archive#5363.

Synchronize harder to avoid excessive spins, invokations of async
callback and sporadic assertion failures on double-call of async
callback.

On Linux, the accept() and accept4() system calls checks for EMFILE
before checking for EAGAIN. Refine our EMFILE error handling tactic
to deal with that. Here is what used to happen:

 1. The event loop calls accept() and sees EMFILE.

 2. Libuv switches to EMFILE error handling mode. It closes a stashed
    file descriptor and calls accept() again.

 3. The accept() system call fails with EAGAIN.

 4. Libuv reopens the stashed file descriptor (reaching RLIMIT_NOFILE
    again) and returns control to the regular event loop.

 5. The regular event loop calls accept(), sees EMFILE and jumps to
    step 2 again. Effectively an infinite loop.

Avoid that by not calling accept() again when we've seen EAGAIN.

Fixes nodejs/node-v0.x-archive#5389.

Conflicts:
	ChangeLog
	src/version.c