Add CMake build system.

Added multiple CMake-related files to project.
Supports building the library and the tests.
See CMakeLists.txt for notes on how it works.

I had to adjust 3 existing files in order to disable some configuration
that should be taken care of by cmake/automake anyway.

I also added jansson.def from a future jansson version,
to test cmake's support for .def files (which works fine).
Fixes for cmake for MSVC2010
Consolidated the CMake project.

- Moved everything to one CMakeLists.txt
- Added support for the json_process test suites (instead of just the API
  tests).
- Changed to use the modified json_process version that does away with the
  environment variables (originally written by DanielT).
- Had to exclude "test_memory_funcs" on MSVC, since void pointer
  arithmetics are not allowed as it is done in secure_malloc and
  secure_free.
- Had to add a check for "ssize_t". This is not available on Windows and
  maybe on some other platforms (used in test_pack.c)
- Result from running ctest (The failure seems unrelated to CMake, it's
  just that the expected result is in a different order):
99% tests passed, 1 tests failed out of 121

Total Test time (real) =   1.31 sec

The following tests FAILED:
         24 - valid__complex-array (Failed)
Always use LF as line ending so that we don't get any problems with line
endings in any tests.
Rename the CMakeModules directory to simply cmake.

This is more consistent with the other directories in the project.
Fix incorrect cast to ssize_t.

gcc 4.2.1 warns about a possible incorrect cast to ssize_t when comparing against refcount, which is of type size_t. signed vs unsigned comparison.

Sinc warnings are treated as errors (as in the autoconf project) this would cause a compile error.
Compile tests by default.

- Encourage actually using the unit tests by compiling them by default.
Set the WITHOUT_TESTS variable to build without instead...

- Changed comments to keep within 80 characters.
- Don't have a hard coded path for valgrind, simply assuem it's in the path instead (an OSX ports install puts it in /opt/local/bin for instance).
- Fixed building the shared lib.
Skip using a debug postfix with visual studio.

The output dir is different anyway, and this just makes it more
complicated to build projects that link to this, because they need
different link rules based on the build type.
Get rid of type warning on MSVC.

We should use json_int_t instead of int, since this can be different
depending on platform. Also MSVC warns that this can cause "loss of
information" since it's converting long long to int.
Moved *config.h.cmake to the cmake directory.
Use json_decref() properly in tutorial
Merge branch '2.4'
Add back the old ENV variabe approach to json_process.

Enable using the old envrionment variable passing of settings for json_process
so that the current autoconf test suite scripts can run nicely.

json_process now takes an optional command line parameter --env which
causes it to use the old method of reading the settings from
environment variables instead of directly from the "env" file.

Also added a --strip command line option, this will be used to
run the stripped tests with CMake as well.
Got rid of some warnings for unused variables.
Merge branch 'rebased_cmake_patch' of git://github.com/JoakimSoderberg/jansson
cmake: Add stripped tests
Remove trailing whitespace
Fix a refleak in test/bin/json_process.c
Do not define _GNU_SOURCE is already defined
Create Android.mk, preconfigured jansson_config.h and CleanSpec.mk for Android-like build systems.