Make template compiler emit element namespace

[pmdartus]

In order to support SVG tags in the template, the engine traverses it's VNodes when evaluating the template and adds the namespace to each VNode. This is work that can be off-loaded to the compiler.

lwc/packages/@lwc/engine/src/framework/api.ts

Lines 300 to 307 in b32da03

	if (
	sel.length === 3 &&
	StringCharCodeAt.call(sel, 0) === CHAR_S &&
	StringCharCodeAt.call(sel, 1) === CHAR_V &&
	StringCharCodeAt.call(sel, 2) === CHAR_G
	) {
	addNS(vnode);
	}

Another benefit of doing this is that LWC would support MathML elements which is not the case today.