http: improve chunked res.write(buf) performance

Avoid a costly buffer-to-string operation. Instead, allocate a new
buffer, copy the chunk header and data into it and send that.

The speed difference is negligible on small payloads but it really
shines with larger (10+ kB) chunks. benchmark/http/end-vs-write-end
with 64 kB chunks gives 45-50% higher throughput. With 1 MB chunks,
the difference is a staggering 590%.

Of course, YMMV will vary with real workloads and networks but this
commit should have a positive impact on CPU and memory consumption.

Big kudos to Wyatt Preul (@wpreul) for reporting the issue and providing
the initial patch.

Fixes #5941 and #5944.
events: fix memory leak, don't leak event names

Before this commit, events were set to undefined rather than deleted
from the EventEmitter's backing dictionary for performance reasons:
`delete obj.key` causes a transition of the dictionary's hidden class
and that can be costly.

Unfortunately, that introduces a memory leak when many events are added
and then removed again. The strings containing the event names are never
reclaimed by the garbage collector because they remain part of the
dictionary.

That's why this commit makes EventEmitter delete events again. This
effectively reverts commit 0397223.

Fixes #5970.
test: fix pummel/test-net-connect-memleak

* Run the garbage collector before creating the big array. It doesn't
  matter now but if in the future something in node.js core creates
  a lot of reclaimable garbage, that will break the test's expectation.

* The first RSS check was being done too late. The garbage collector
  might have run before the check, throwing off the 'reclaimed memory'
  calculation.

* Due to changes in how V8 represents the big array internally, the
  actual memory usage is just below 256 MB on x64. Update the test's
  expectation.
test: future-proof simple/test-event-emitter-memory-leak

Run the garbage collector before running the actual test. It doesn't
matter now but if in the future something in node.js core creates a lot
of reclaimable garbage, that will break the test's expectation.
npm: Upgrade to 1.3.7
doc: fs.open, fix flag/mode confusion, etc.

Flags and modes aren't the same, symlinks are followed in all of the
path but the last component, docs should say something about what the
mode argument is for and when its used, fs.openSync should point to the
function that contains the docs for its args, as fs.writeSync does.
doc: document domain.enter() and domain.exit()

Adds the documentation requested in #5017.
v8: back-port fix for CVE-2013-2882

Quoting the CVE:

    Google V8, as used in Google Chrome before 28.0.1500.95, allows
    remote attackers to cause a denial of service or possibly have
    unspecified other impact via vectors that leverage "type confusion."

Likely has zero impact on node.js because it only runs local, trusted
code but let's apply it anyway.

This is a back-port of upstream commit r15665. Original commit log:

    Use internal array as API function cache.

    R=yangguo@chromium.org
    BUG=chromium:260106
    TEST=cctest/test-api/Regress260106

    Review URL: https://codereview.chromium.org/19159003

Fixes #5973.
doc: Update LICENSE for npm's Artistic 2.0
stream: Fix double pipe error emit

If an error listener is added to a stream using once() before it is
piped, it is invoked and removed during pipe() but before pipe() sees it
which causes it to be emitted again.

Fixes #4155 #4978
blog: Post for v0.11.5
http: Handle hex/base64 encodings properly

This is a backport of 6d3d60aced39d59eaa5e705b7d822c227d0d3dae for
v0.10.
crypto: fix memory leak in randomBytes() error path

This is the conceptual back-port of commit ec54873 from the master
branch.
npm: Upgrade to 1.3.8
2013.08.16, Version 0.10.16 (Stable)

* v8: back-port fix for CVE-2013-2882

* npm: Upgrade to 1.3.8

* crypto: fix assert() on malformed hex input (Ben Noordhuis)

* crypto: fix memory leak in randomBytes() error path (Ben Noordhuis)

* events: fix memory leak, don't leak event names (Ben Noordhuis)

* http: Handle hex/base64 encodings properly (isaacs)

* http: improve chunked res.write(buf) performance (Ben Noordhuis)

* stream: Fix double pipe error emit (Eran Hammer)
Merge branch 'v0.10.16-release' into v0.10
Now working on v0.10.17
blog: v0.10.16
readline: pause stdin before turning off terminal raw mode

On windows, libuv will immediately make a `ReadConsole` call (in the
thread pool) when a 'flowing' `uv_tty_t` handle is switched to
line-buffered mode. That causes an immediate issue for some users,
since libuv can't cancel the `ReadConsole` operation on Windows 8 /
Server 2012 and up if the program switches back to raw mode later.

But even if this will be fixed in libuv at some point, it's better to
avoid the overhead of starting work in the thread pool and immediately
cancelling it afther that.

See also f34f1e3, where the same change is made for the opposite
flow, e.g. move `resume()` after `_setRawMode(true)`.

Fixes #5927

This is a backport of dfb0461 (see #5930) to the v0.10 branch.
dgram: fix assertion on bad send() arguments

Add range checks for the offset, length and port arguments to
dgram.Socket#send().  Fixes the following assertion:

    node: ../../src/udp_wrap.cc:264: static v8::Handle<v8::Value>
    node::UDPWrap::DoSend(const v8::Arguments&, int): Assertion
    `offset < Buffer::Length(buffer_obj)' failed.

And:

    node: ../../src/udp_wrap.cc:265: static v8::Handle<v8::Value>
    node::UDPWrap::DoSend(const v8::Arguments&, int): Assertion
    `length <= Buffer::Length(buffer_obj) - offset' failed.

Interestingly enough, a negative port number was accepted until now but
silently ignored.  (In other words, it would send the datagram to a
random port.)

This commit exposed a bug in the simple/test-dgram-close test which
has also been fixed.

This is a back-port of commit 41ec6d0 from the master branch.

Fixes #6025.