Add more links and fix translations in About page

[inson1]

fixes: #89 fixes: #90

!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Add to weblate, please :)

"aboutTranslationsLabel":{
    "message": "Translations",
    "description": "The label for Translations in About page"
},
"aboutLicenseLabel":{
    "message": "Licence AGPL v3",
    "description": "The label for License in About page"
},
"aboutChangelogLabel":{
    "message": "Changelog",
    "description": "The label for Changelog in About page"
},
"aboutSourceCodeLabel":{
    "message": "Source code",
    "description": "The label for Source code in About page"
}

[inson1]

I still have to test it, but I dont see any problem

[navorite]

Make me able to add commits to your PR to do this

[navorite]

you still don't have the correct order

[inson1]

@navorite What order would you propose?