Merge branch 'tag-cloud' into 'staging'

Merge branch 'tag-cloud' into 'staging'

Closes #99, #98, #77, #76, #75, #74, #73, #69, #57, #42, #33, #32, #30, #23, #16, #15, #14, #8, #7, #97, #89, and #78

See merge request arsnova/topic-cloud!42