refractor: accounting module (#300)

* Refractor components.
* Add resolvers.
* Add relative router links.
* Replace mat-icons by font-awesome icons.
* Add comments.

Fixes: #298

src/app/accounting/closing-entries/view-closure/view-closure.component.scss

@@ -1,14 +1,14 @@
 .container {
   max-width: 37rem;
-}
 
-.content {
-  div {
-    margin: 1rem 0;
-    word-wrap: break-word;
-  }
+  .content {
+    div {
+      margin: 1rem 0;
+      word-wrap: break-word;
 
-  .header {
-    font-weight: 500;
+      &.header {
+        font-weight: 500;
+      }
+    }
   }
 }