Fix SendGetGroups Function
Fix SendGetGroups Function

The value "participating" has to be the Tag and not a child of
attributeHash.
And the attributeHash has to be null

rvriens/Chat-API-NET,rvriens/Chat-API-NET,mgp25/Chat-API-NET,mgp25/Chat-API-NET,andrebires/Chat-API-NET,blachshma/Chat-API-NET,andrebires/Chat-API-NET,mgp25/Chat-API-NET,kienct89/Chat-API-NET,rvriens/Chat-API-NET,andrebires/Chat-API-NET