Added monolog to the tested frameworks

Added [monolog](https://github.com/Seldaek/monolog) (current stable version - 1.7) to the tested frameworks. Monolog is the defacto default logging library for Symfony2/Silex/... based applications.

Everything looks well expect 3 failing unit-test. The failing tests seem to be related to a unsupported syntax for `DateTime`. When you pass in `@<int>` in PHP you get the Unix-timestamp with *timezone set to GMT+0*. In HHVM the timezone is kept at the configured timezone.


Test script:

    <?php
    
    $d = new DateTime("@0");
    echo $d->format('c'), "\n";

Results:

    bz@hhvm-dev:~/hhvm$ date
    Fr 20. Dez 10:25:27 CET 2013

    bz@hhvm-dev:~/hhvm$ php test.php
    1970-01-01T00:00:00+00:00
    
    bz@hhvm-dev:~/hhvm$ hhvm test.php
    1970-01-01T00:00:00+01:00



I couldn't find an existing issue for this problem - do you want me to open one?


Failing tests:

    1) Monolog\Formatter\LogstashFormatterTest::testDefaultFormatter
    
    RUN TEST FILE:  cd /home/bz/hhvm/hphp/test/frameworks/frameworks/monolog && /home/bz/hhvm/hphp/test/frameworks/../../hhvm/hhvm -v Repo.Local.Mode=-- -v Repo.Central.Path=/tmp/framework-testE800ie --config /home/bz/hhvm/hphp/test/frameworks/config.hdf -v Server.IniFile=/home/bz/hhvm/hphp/test/frameworks/php.ini -v Eval.Jit=true /home/bz/hhvm/hphp/test/frameworks/vendor/bin/phpunit --debug -c /home/bz/hhvm/hphp/test/frameworks/frameworks/monolog/phpunit.xml.dist --filter 'Monolog\\Formatter\\LogstashFormatterTest::testDefaultFormatter'
    
    Failed asserting that two strings are equal.
    --- Expected
    +++ Actual
    @@ @@
    -'1970-01-01T00:00:00.000000+00:00'
    +'1970-01-01T00:00:00.000000-08:00'
    
    /home/bz/hhvm/hphp/test/frameworks/frameworks/monolog/tests/Monolog/Formatter/LogstashFormatterTest.php:38
    /home/bz/hhvm/hphp/test/frameworks/vendor/phpunit/phpunit/PHPUnit/TextUI/Command.php:176
    /home/bz/hhvm/hphp/test/frameworks/vendor/phpunit/phpunit/PHPUnit/TextUI/Command.php:129
    
    2) Monolog\Formatter\LogstashFormatterTest::testDefaultFormatterV1
    
    RUN TEST FILE:  cd /home/bz/hhvm/hphp/test/frameworks/frameworks/monolog && /home/bz/hhvm/hphp/test/frameworks/../../hhvm/hhvm -v Repo.Local.Mode=-- -v Repo.Central.Path=/tmp/framework-testE800ie --config /home/bz/hhvm/hphp/test/frameworks/config.hdf -v Server.IniFile=/home/bz/hhvm/hphp/test/frameworks/php.ini -v Eval.Jit=true /home/bz/hhvm/hphp/test/frameworks/vendor/bin/phpunit --debug -c /home/bz/hhvm/hphp/test/frameworks/frameworks/monolog/phpunit.xml.dist --filter 'Monolog\\Formatter\\LogstashFormatterTest::testDefaultFormatterV1'
    
    Failed asserting that two strings are equal.
    --- Expected
    +++ Actual
    @@ @@
    -'1970-01-01T00:00:00.000000+00:00'
    +'1970-01-01T00:00:00.000000-08:00'
    
    /home/bz/hhvm/hphp/test/frameworks/frameworks/monolog/tests/Monolog/Formatter/LogstashFormatterTest.php:179
    /home/bz/hhvm/hphp/test/frameworks/vendor/phpunit/phpunit/PHPUnit/TextUI/Command.php:176
    /home/bz/hhvm/hphp/test/frameworks/vendor/phpunit/phpunit/PHPUnit/TextUI/Command.php:129
    
    1) Monolog\Formatter\ElasticaFormatterTest::testFormat
    
    RUN TEST FILE:  cd /home/bz/hhvm/hphp/test/frameworks/frameworks/monolog && /home/bz/hhvm/hphp/test/frameworks/../../hhvm/hhvm -v Repo.Local.Mode=-- -v Repo.Central.Path=/tmp/framework-testE800ie --config /home/bz/hhvm/hphp/test/frameworks/config.hdf -v Server.IniFile=/home/bz/hhvm/hphp/test/frameworks/php.ini -v Eval.Jit=true /home/bz/hhvm/hphp/test/frameworks/vendor/bin/phpunit --debug -c /home/bz/hhvm/hphp/test/frameworks/frameworks/monolog/phpunit.xml.dist --filter 'Monolog\\Formatter\\ElasticaFormatterTest::testFormat'
    
    Failed asserting that two strings are equal.
    --- Expected
    +++ Actual
    @@ @@
    -'1970-01-01T00:00:00+0000'
    +'1970-01-01T00:00:00-0800'
    
    /home/bz/hhvm/hphp/test/frameworks/frameworks/monolog/tests/Monolog/Formatter/ElasticaFormatterTest.php:66
    /home/bz/hhvm/hphp/test/frameworks/vendor/phpunit/phpunit/PHPUnit/TextUI/Command.php:176
    /home/bz/hhvm/hphp/test/frameworks/vendor/phpunit/phpunit/PHPUnit/TextUI/Command.php:129


Runner result:

    bz@hhvm-dev:~/hhvm$ hhvm hphp/test/frameworks/run.php monolog
    monolog: running. Comparing against 256 tests
    Beginning the unit tests.....
    ........................................................................................................................................................................    ........................................................................................
    All tests ran as expected.
    
              _
             /(|
            (  :
           __\  \  _____
         (____)  -|
        (____)|   |
         (____).__|
          (___)__.|_____
    
    ALL TESTS COMPLETE!
    SUMMARY:
    monolog=98.41
    
    To run differing tests (if they exist), see above for the
    commands or the results/.diff file. To run erroring or
    fataling tests see results/.errors and results/.fatals
    files, respectively