Fix some linting errors.

src/cookie-handler.ts

@@ -21,7 +21,7 @@ export class CookieHandler {
 
     getLayout(): string {
         const oldCookie = this.getCookie('uhr-language');
-        if (!!oldCookie) {
+        if (oldCookie) {
             // aha, old cookie is set. migrate to new one!
             this.removeCookie('uhr-language');
             this.setLayout(oldCookie);
@@ -64,7 +64,7 @@ export class CookieHandler {
 
     private setCookie(cookieName: string, cookieValue: string): void {
         let options;
-        if (!!this.cookiePath) {
+        if (this.cookiePath) {
             options = {expires: 365, path: this.cookiePath};
         } else {
             options = {expires: 365};
@@ -73,7 +73,7 @@ export class CookieHandler {
     }
 
     private removeCookie(cookieName: string): void {
-        if (!!this.cookiePath) {
+        if (this.cookiePath) {
             Cookies.remove(cookieName + this.widgetId, {path: this.cookiePath});
         } else {
             Cookies.remove(cookieName + this.widgetId);

src/domain/letter.ts

@@ -24,7 +24,7 @@ export class Letter {
 
     constructor(value: string, style?: string) {
         this.value = value;
-        if (!!style) {
+        if (style) {
             this.style = style;
         }
     }
@@ -35,9 +35,9 @@ export class Letter {
         } else {
             this.style += ` ${style}`;
         }
-    };
+    }
 
     toString(): string {
         return `<span class="item letter ${this.style}">${this.value}</span>`;
-    };
+    }
 }

src/layout-renderer.ts

@@ -245,7 +245,7 @@ class LayoutRendererV2Delegate {
         this.parseTimeDefinition(letters, 'minute', this.layout.minutes);
         this.parseTimeDefinition(letters, 'hour', this.layout.hours);
         return letters;
-    };
+    }
 
     private parseObject(letters: Letter[][], styleClass: string, object: WordDefinition): void {
         if (typeof object !== 'undefined' && object !== null) {
@@ -313,10 +313,10 @@ export class LayoutRenderer {
                     this.renderarea.append('<br/>');
                 }
             });
-            if (!!beforeshow) {
+            if (beforeshow) {
                 beforeshow();
             }
             this.renderarea.fadeIn('fast');
         });
-    };
+    }
 }

src/uhr-renderer.ts

@@ -97,7 +97,7 @@ export class UhrRenderer {
             configlink.on({click: () => this.toggleConfigScreen()});
             this.$element.after(configlink);
         }
-    };
+    }
 
     private wireFunctionality(): void {
         // on/off switch
@@ -203,5 +203,5 @@ export class UhrRenderer {
 
     private toggleConfigScreen() {
         $(`#uhr-controlpanel${this.id}`).toggle('fast');
-    };
+    }
 }

src/uhr.ts

@@ -42,7 +42,7 @@ export class Uhr {
     }
 
     destroy(): void {
-        if (!!this.timer) {
+        if (this.timer) {
             window.clearInterval(this.timer);
             this.timer = null;
         }