Adding Netgiro integration

Signed-off-by: Sævar Öfjörð Magnússon <saevar@overcast.io>
More testing

Signed-off-by: Sævar Öfjörð Magnússon <saevar@overcast.io>
Update CONTRIBUTORS

Signed-off-by: Sævar Öfjörð Magnússon <saevar@overcast.io>
Debug

Signed-off-by: Sævar Öfjörð Magnússon <saevar@overcast.io>
Added additional Netgiro options and tests

Signed-off-by: Sævar Öfjörð Magnússon <saevar@overcast.io>
Add Netgíró to the list of offsite integrations

Signed-off-by: Sævar Öfjörð Magnússon <saevar@overcast.io>