Add changelog to the module metadata

[Alex-developer]

Add structured changelog data to the module meta data. This will allow

1. Details of the module changes to be displayed in the module manager
2. Contributors to be credited

NOTE: This will require changes to the core Allsky code as well to display the changelog

Example json

changelog": { 
        "v1.0.0" : [  
            {
                "author": "Alex Greenland",
                "authorurl": "https://github.com/allskyteam",
                "change": "Initial Release"
            }
        ],
        "v1.0.1" : [
            {
                "author": "Damian Grocholski (Mr-Groch)",
                "authorurl": "https://github.com/Mr-Groch",
                "changes": [
                    "Added extra pin that is triggered with heater pin",
                    "Fixed dhtxxdelay (was not implemented)",
                    "Fixed max heater time (was not implemented)"
                ]
            }
        ],
        "v1.0.2" : [
            {
                "author": "Alex Greenland",
                "authorurl": "https://github.com/allskyteam",
                "change": "Initial Release"
            }
        ],
        "v1.0.3" : [
            {
                "author": "Alex Greenland",
                "authorurl": "https://github.com/allskyteam",
                "change": "Add AHTx0 i2c sensor"
            }
        ],
        "v1.0.4" : [
            {
                "author": "Alder6907",
                "authorurl": "https://github.com/Adler6907",
                "change": "Added Solo Cloudwatcher"
            }
        ]                                
    }