More appropriate error messages for snapshot service
Merge pull request #582 from gjn/dev_snapshot_bettererrors

More appropriate error messages for snapshot service
Add new attribut in Model + add mailto link if resolution is not 0.25 or 0.5
Replace 'td' by 'th' and align source code
Merge pull request #585 from geoadmin/data_#1335_Lubis_Email_Link

replace link to toposhop with a mailto if iamge resolution is not 0.25 or 0.5
Add translation for attribution swisstopo private
Merge pull request #586 from geoadmin/data_#1334_New_Attribution

Add translation for attribution swisstopo private