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/accounting.component.ts

@@ -1,5 +1,9 @@
+/** Angular Imports */
 import { Component, OnInit } from '@angular/core';
 
+/**
+ * Accounting component.
+ */
 @Component({
   selector: 'mifosx-accounting',
   templateUrl: './accounting.component.html',