added 'goal' field to project (only set in get_project_by_url atm, not available in ks searchresults...)
removed 'ref' parameter from project url in search_projects
added search offset parameter to search_projects
Merge pull request #1 from RoelVG/master

Merging pull request #1 => added goal field to Project class; removal of GET URL parameters in the project URL; Added offset to search_projects method