Add information about installing dev environment on OS X
Remove old OS X 'instructions'
Lots of build system and docs improvements, including a manpage.

 - Build binaries for multiple platforms
 - Make a manpage out of the manual (see #19)
 - Extract more tests from the documentation
 - Fix a few documentation bugs uncovered by above.
Fix a bug uncovered by tests extracted from manual.

`null | length` should give 0, and now does.
Improve manpage introduction, add examples to manpage.

Closes #19
Add the ability to specify input files on the commandline.

See #21.
Add wrappers for malloc/realloc/free. See #43.
Print an error message and abort in out-of-memory situations.

Closes #43.

Tested with:

    ulimit -v 5000
    ./jq -n -c 'def f(x): x,f([x,x]); f(0)'
Fix a bug in stack reallocation during deep recursion.
Merge pull request #50 from stesh/master

Add information about installing dev environment on OS X
Don't enable coloured output by default on Windows.
Update download page and build system to handle more platforms.
Add a few lines to the bottom of the manpage.
Version 1.2!
Give Windows builds a proper .exe suffix.
Fix a bad memory leak when using --raw-output
Sneaky valgrind trick to detect stack memory issues.

After something is popped from a stack, we overwrite the memory
with uninitialised data (if JQ_DEBUG is on). This means that
valgrind reports use-after-pop as an uninitialised memory error.
JSON parsing error messages now specify a location of the error.

Should help with #53.
Fix an embarassing I/O bug.

Pulling some I/O out to a function meant that buf changed from
"char buf[4096]" to "char* buf", and "sizeof(buf)" got a lot
less interesting. The upshot of this is that jq read input eight
bytes at a time, which is not the fastest.
@foo syntax for encoding of strings into various formats.

Fixes part of #47 and #48.