Added version display to options page.

As suggested in #221.

options/options.css

@@ -186,4 +186,10 @@ td.hideColumn {
 }
 .content .hide:checked ~ .display, .displayHidden:checked ~ .display {
 	background-image: url(notVisible.svg);
+}
+
+.version {
+	text-align: right;
+	color: gray;
+	font-size: 0.8em;
 }

options/options.js

@@ -199,4 +199,13 @@
 			}
 		}
 	});
+	
+	const version = document.createElement("div");
+	version.className = "version";
+	fetch(browser.extension.getURL("manifest.json")).then(function(response){
+		return response.json();
+	}).then(function(manifest){
+		version.textContent = "Version " + manifest.version;
+	});
+	document.body.appendChild(version);
 }());

releaseNotes.txt

@@ -3,7 +3,7 @@ Version 0.5.3:
 		- 
 	
 	new features:
-		- 
+		- display version in options page
 	
 	fixes:
 		-