refacter method "innerAddSpan".
create a function 'parseParagraphs' from 'makeParagraphs'.
'parseParagraphs' parse sourceDoc.
'makeParagraphs' render p tag and chache element.
move function 'renderer.paragraphs.getBySid' to 'render.getParagraphId'.
refactor getRangeToInsertSpanTag.
cache paragraph in span.
thre is no big brother if the span is first in a paragrpah.
create method to push typesPerSpan and entitiesPerType.
create methods to edit typesPerSpan.
move typesPerSpan into model.annotationData .
typesPerSpan change span's property.