feat(rest): document historic process instance query

related to CAM-1153
feat(rest): document historic activity instance query

related to CAM-1153
feat(rest): document historic variable instance query

related to CAM-1153
chore(rest): update embeddability chapter
chore(rest): document process instance filtering by IDs

related to CAM-1153
Merge branch 'master' of github.com:camunda/docs.camunda.org