* Remove the hardcoded text for the two buildings
that had this already hardcoded in their description.
* Add parsing for the `<TerritoryInfluence>` tag to the
template loader.
* Add new tooltip function that can return a "Territory Influence"
heading with text similar to the previous text that was hardcoded
(made more generic so as to not assume it is a monument).
* Use the new tooltip function for the tech tree (draw.js),
for the construction icon (selection_panels.js),
for the existing building (selection_details.js).
* Use the new tooltip function for the tech tree (draw.js).
Fixes #4259.
(WARNING)
**TODO**: Works in tech tree, but not yet in the construction tooltipAdd it to "more information" dialog as well.