feat(svg_icon): Add standard svg icons

-Adds icons to use with the svg_icon smarty helper in the is_themecore module. See is_themecore-PS9 repo.

- Uses chevron svg icons by default on bootstrap touchspin AND on main menu if it has children.

falcon/_dev/img/person.svg

@@ -0,0 +1,6 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="18.506" height="20.5" viewBox="0 0 18.506 20.5">
+  <g id="Icon_akar-person" data-name="Icon akar-person" transform="translate(-4.145 -2.25)">
+    <path id="Path_18" data-name="Path 18" d="M20.4,7.75a4.854,4.854,0,0,1-4.952,4.75A4.854,4.854,0,0,1,10.5,7.75,4.854,4.854,0,0,1,15.452,3,4.854,4.854,0,0,1,20.4,7.75Z" transform="translate(-2.054)" fill="none" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round" stroke-width="1.5"/>
+    <path id="Path_19" data-name="Path 19" d="M18.264,21h.343a2.9,2.9,0,0,1,2.9,2.5l.381,2.968a1.87,1.87,0,0,1-.472,1.493,1.967,1.967,0,0,1-1.459.642H6.845a1.967,1.967,0,0,1-1.46-.643,1.87,1.87,0,0,1-.472-1.493l.38-2.968a2.9,2.9,0,0,1,2.9-2.5h.342" transform="translate(0 -6.6)" fill="none" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round" stroke-width="1.5"/>
+  </g>
+</svg>