Portal history in IITC

[mrWhitton]

To build functionality for the new portal history in IITC.
https://community.ingress.com/en/discussion/13451/portal-history-now-available-on-intel-map/p1?new=1

[ekuinox]

ingress-intel-total-conversion/code/entity_decode.js

Lines 97 to 111 in a34df32

	window.decodeArray.portalSummary = function(a) {
	if (!a) return undefined;
	if (a[0] != 'p') throw 'Error: decodeArray.portalSUmmary - not a portal';
	if (a.length == CORE_PORTA_DATA_LENGTH) {
	return corePortalData(a);
	}
	// NOTE: allow for either summary or detailed portal data to be passed in here, as details are sometimes
	// passed into code only expecting summaries
	if (a.length != SUMMARY_PORTAL_DATA_LENGTH && a.length != DETAILED_PORTAL_DATA_LENGTH) {
	console.warn('Portal summary length changed - portal details likely broken!');
	debugger;
	}

when portal level is none a.length may be 14. but when portal was visited or captured, scout controlled, a.length may be 19.
I infer a[18] means level.
https://twitter.com/remokusu/status/1357929670994391041

[johnd0e]

Duplicate of #1315