Feature/add refactoring

more tidy code and partly refactor functions for tei:add

• rename prefix fom fontaneTransfo to transfo
• remove small space around tei:add
• remove the xhtml:span[@class="addWrapper"] as it is completely unhandy
• rewritten functions for tei:add
  • we are using the same function for anchored and non-anchored tei:add now
  • merge 3 functions to 2

there is a corresponding MR at SADE-Project!4 (merged)