[gui] building → structure
This patch corrects occurrences of “building” into “structure”.
Whilst “constructing a building” is proper English, it is important to refer to one and the same thing with a single term, to avoid potential misunderstandings (see https://trac.wildfiregames.com/wiki/EnglishStyleGuide ), thence “building a structure”, because the unit action is “build” and the entity is a “structure” (see simulation/templates/).
Test Plan: Check for mistakes and omissions.
Reviewed By: Gallaecio
Subscribers: Freagarach, O8 JS GUI
Differential Revision: https://code.wildfiregames.com/D2429