Bunyan

- [issue 165] Include extra `err` fields in `bunyan` CLI output. Before
this change only the fields part of the typical node.js error stack
(err.stack, err.message, err.name) would be emitted, even though
the Bunyan *library* would typically include err.code and err.signal
in the raw JSON log record.

- Fix a breakage in `log.info(err)` on a logger with no serializers.

Note: *Bad release.* It breaks `log.info(err)` on a logger with no serializers.
Use version 1.1.2.

- [pull 168] Fix handling of `log.info(err)` to use the `log` Logger's `err`
serializer if it has one, instead of always using the core Bunyan err
serializer. (By Mihai Tomescu.)

- [issue 162] Preliminary support for [browserify](http://browserify.org/).
See [the section in the README](../README.mdbrowserify).

- [issues 105, 138, 151] Export `<Logger>.addStream(...)` and
`<Logger>.addSerializers(...)` to be able to add them after Logger creation.
Thanks andreineculau!

- [issue 159] Fix bad handling in construtor guard intending to allow
creation without "new": `var log = Logger(...)`. Thanks rmg!

- [issue 156] Smaller install size via .npmignore file.

- [issue 126, 161] Ignore SIGINT (Ctrl+C) when processing stdin. `...| bunyan`
should expect the preceding process in the pipeline to handle SIGINT. While
it is doing so, `bunyan` should continue to process any remaining output.
Thanks timborodin and jnordberg!

- [issue 160] Stop using ANSI 'grey' in `bunyan` CLI output, because of the
problems that causes with Solarized Dark themes (see
<https://github.com/altercation/solarized/issues/220>).

- [issue 87] **Backward incompatible change to `-c CODE`** improving
performance by over 10x (good!), with a backward incompatible change to
semantics (unfortunate), and adding some sugar (good!).

The `-c CODE` implementation was changed to use a JS function for processing
rather than `vm.runInNewContext`. The latter was specatularly slow, so
won't be missed. Unfortunately this does mean a few semantic differences in
the `CODE`, the most noticeable of which is that **`this` is required to
access the object fields:**

Bad. Works with bunyan 0.x but not 1.x.
$ bunyan -c 'pid === 123' foo.log
...

Good. Works with all versions of bunyan
$ bunyan -c 'this.pid === 123' foo.log
...

The old behaviour of `-c` can be restored with the `BUNYAN_EXEC=vm`
environment variable:

$ BUNYAN_EXEC=vm bunyan -c 'pid === 123' foo.log
...

Some sugar was also added: the TRACE, DEBUG, ... constants are defined, so
one can:

$ bunyan -c 'this.level >= ERROR && this.component === "http"' foo.log
...

And example of the speed improvement on a 10 MiB log example:

$ time BUNYAN_EXEC=vm bunyan -c 'this.level === ERROR' big.log | cat >slow

real 0m6.349s
user 0m6.292s
sys 0m0.110s

$ time bunyan -c 'this.level === ERROR' big.log | cat >fast

real 0m0.333s
user 0m0.303s
sys 0m0.028s

The change was courtesy Patrick Mooney (https://github.com/pfmooney). Thanks!

- Add `bunyan -0 ...` shortcut for `bunyan -o bunyan ...`.

- [issue 135] **Backward incompatible.** Drop dtrace-provider even from
`optionalDependencies`. Dtrace-provider has proven a consistent barrier to
installing bunyan, because it is a binary dep. Even as an *optional* dep it
still caused confusion and install noise.

Users of Bunyan on dtrace-y platforms (SmartOS, Mac, Illumos, Solaris) will
need to manually `npm install dtrace-provider` themselves to get [Bunyan's
dtrace support](https://github.com/trentm/node-bunyanruntime-log-snooping-via-dtrace)
to work. If not installed, bunyan should stub it out properly.