Change KnockoutJS to just warn for missing Observables.

Sieve doesn't need them, for now.

dev/Sieve/Grammar.js

@@ -9,7 +9,7 @@ import {
 	MULTILINE_DOTSTART
 } from 'Sieve/RegEx';
 
-import { arrayToString, getMatchTypes, getComparators, koObserve } from 'Sieve/Utils';
+import { arrayToString, getMatchTypes, getComparators } from 'Sieve/Utils';
 
 /**
  * abstract
@@ -154,7 +154,6 @@ export /*abstract*/ class TestCommand extends GrammarCommand
 		this._comparator = '';
 		this._match_type = '';
 		this.relational_match = ''; // GrammarQuotedString DQUOTE ( "gt" / "ge" / "lt" / "le" / "eq" / "ne" ) DQUOTE
-		koObserve(this, 'match_type');
 	}
 
 	get require() { return /:value|:count/.test(this._match_type) ? 'relational' : ''; }

dev/Sieve/Utils.js

@@ -58,18 +58,6 @@ export const
 		serverErrorDesc(text);
 	},
 
-	koObserve = (obj, prop) => {
-//		Object.getOwnPropertyNames(obj).forEach(prop => {
-//			prop = prop.replace(/^_/, '');
-			obj['ko_' + prop] = ko.computed({
-				read: () => obj[prop],
-				write: (v) => obj[prop] = v,
-				pure:true
-			});
-//		});
-//		Object.preventExtensions(obj);
-	},
-
 	getComparators = (validOnly = 0) => {
 		let result = [
 			// Default