Add sub/superscript in RichText

Merge pull request elapouya#145 from jsve/add-subscript-and-superscri…

…pt-to-list-of-styling-props

added props for sub and super

Merge pull request elapouya#142 from nickgashkov/fix/vmerge-w-t-attri…

…butes

Fix vertical merge tag for table cells with XML attributes

Testing new cell vertical merge

Merge pull request elapouya#124 from isaacsucn/master

Insert exist document as subdocument

Merge pull request elapouya#123 from f1remind/master

Experimental font option for RichText objects

Fix runtests.py

Accept variables starting with 'r' in {{}} when no space after {{

Merge pull request elapouya#100 from anselal/patch-1

Fix minor typo

Remove debug traces