Preserve the content around the template

[thejonan]

Currently a template is assumed that occupies the whole cell, and even if there is content around it - it is overwritten by the data placement mechanism.

It will be more convenient to be able to preserve the fixed content around it, and - of course - multiply it along the other cells, depending on the data size(s).

There are couple of caveats:

• The original content of the template's cell is overwritten because of normal data placement - it needs to be stored aside. Easy.
• The content can be RichText based, and it should stay that way, making the "find-and-replace" act a bit more difficult. Not impossible.