Including the first working version of NagiosWriter.

Conf example:
{ "outputWriters" : [ {
    "@class" : "com.googlecode.jmxtrans.model.output.NagiosWriter",
    "settings" : {
        "typeNames" : [ "name" ],
        "outputFile": "/tmp/denis_jmx",
        "nagiosHost": "HOSTNAME",
        "prefix": "Pre ",
        "posfix": " Pos",
        "filters": ["HeapMemoryUsage_used", "NonHeapMemoryUsage_max"],
        "thresholds": ["@1000000000:3000000000,", ""]
    }
    } ],
    "obj" : "java.lang:type=Memory",
    "resultAlias": "memory",
    "attr" : [ "HeapMemoryUsage", "NonHeapMemoryUsage", "" ]
}

outputFile - Should be the Nagios command file.
    - Cannot be empty.
nagiosHost - The host name defined at Nagios.
    - Cannot be empty.
prefix - Used in the service name to prefix the service description.
    - Can be empty.
posfix - Used in the service name to posfix the service description.
    - Can be empty.
filters - Attr that should be used as a service name.
    -Cannot be empty.
    - Attr HeapMemoryUsage can create 3 outputs:
        - HeapMemoryUsage_used
        - HeapMemoryUsage_min
        - HeapMemoryUsage_max
    For each one that you want to send to Nagios you must include it on filters.
thresholds - It defines the threshold for each filter using the Nagios range definition.
    - Cannot be empty.
    - Syntax:
        - Each threshold has two parts 'warning,critical'
        - Each part can contain a range definition.
            - http://nagiosplug.sourceforge.net/developer-guidelines.html#THRESHOLDFORMAT
        - An empty ("") threshold means always OK.
        - If there is only one field or it starts with comma that service will never be in warning state.
            - "@1000000000"
            - ",@1000000000"
        - If the fields ends with comma that service will never be in critical state:
            - "@1000000000,"

Filters and threholds are bound, so threholds must be in the same position as the filters which it must apply.
Also they must have the same size.
Add OutputWriter implementation for posting metrics to Stackdriver over HTTP.  Update BaseOutputWriter to support numeric settings as well as String settings.
fix typo in log message
Update how we make the metric names, take advantage of the aliases in the config and only add the extra value key to the end if it is different than the attribute name.  Use StringBuilder for efficiency
use up to date GMetrics4j, 1.0.3
add pom.xml reworked from pull-request https://github.com/jmxtrans/jmxtrans/pull/87
Merge pull request #84 from Stackdriver/master

Initial version of OutputWriter for Stackdriver
updated javadoc for StackdriverWriter
Merge pull request #83 from thuck/master

Including the first working version of NagiosWriter.
javadoc regenerated with Java 1.7.0-25, to avoid security issue
Merge branch 'master' of github.com:jmxtrans/jmxtrans