Walls not build if wall tower foundations overlap

[elexis]

As noticed by temple spectating a Hellas game with Emperior, it can occur that wall pieces are not being built following ​Phab:D21 if the obstructions of the wall tower foundations overlap.

This regression must be fixed before the release. The easiest way to accomplish that is making structures not block construction as proposed in ​Phab:D1445 (and the case in a22).

But there is also the question if this ideal. It'd be better if foundations cannot overlap (which was an assumption of ​Phab:D21.)

There is a patch for the templatesanalyzer detecting incompatible lengths at ​Phab:D1440. ​Phab:D1439 changes wall tower lengths to match the obstruction size.

[elexis]

In Walls.js added by r11760:

TODO: make sure intermediate towers are spaced out far enough for their obstructions to not overlap, implying that tower's wallpiece lengths should be > their obstruction width, which is undesirable because it prevents towers with wide bases

[temple]

In 21702:

Make structures not block construction

Differential Revision: ​https://code.wildfiregames.com/D1445
Reviewed by: elexis
Refs: #5118

[elexis]

Thanks for fixing the regression

[Imarok]

Move tickets to Simulation as UI & Simulation got some sub components.