refractor: shell (#287)

* Refractor components.
* Shift theme picker component to shared module.
* Shift progress bar service into its own folder.
* Add footer to app shell.
* Replace mat-icon by font-awesome icons.
* Fix sidenav visibility bug for handsets.
* Add comments.

Closes #286, Fixes #285

src/app/shared/theme-picker/theme-storage.service.ts

@@ -0,0 +1,67 @@
+/** Angular Imports */
+import {Injectable, EventEmitter} from '@angular/core';
+
+/** Custom Model */
+import { Theme } from './theme.model';
+
+/** Custom Services */
+import { ThemeManagerService } from './theme-manager.service';
+
+/**
+ * Theme storage service.
+ */
+@Injectable({
+  providedIn: 'root'
+})
+export class ThemeStorageService {
+
+  /** Key to store current theme of application in local storage. */
+  private themeStorageKey = 'mifosXTheme';
+  /** Theme update event. */
+  onThemeUpdate: EventEmitter<Theme>;
+
+  /**
+   * Initializes theme update event.
+   * @param {ThemeManagerService} themeManagerService
+   */
+  constructor(public themeManagerService: ThemeManagerService) {
+    this.onThemeUpdate = new EventEmitter<Theme>();
+  }
+
+  /**
+   * Stores current theme in local storage and emits a theme update event.
+   * @param mifosXTheme
+   */
+  storeTheme(mifosXTheme: Theme) {
+    localStorage.setItem(this.themeStorageKey, JSON.stringify(mifosXTheme));
+    this.onThemeUpdate.emit(mifosXTheme);
+  }
+
+  /**
+   * @returns current theme from local storage
+   */
+  getTheme(): Theme {
+    return JSON.parse(localStorage.getItem(this.themeStorageKey));
+  }
+
+  /**
+   * Removes current theme from local storage.
+   */
+  clearTheme() {
+    localStorage.removeItem(this.themeStorageKey);
+  }
+
+  /**
+   * Sets a new theme for the application and stores in local storage.
+   * @param {Theme} theme
+   */
+  installTheme(theme: Theme) {
+    if (theme.isDefault) {
+      this.themeManagerService.removeTheme();
+    } else {
+      this.themeManagerService.setTheme(`theme/${theme.href}`);
+    }
+    this.storeTheme(theme);
+  }
+
+}