refractor: login module (#283)

* Refractor components.
* Shift language and footer component to shared module.
* Replace mat-icons by font-awesome icons.
* Add comments.

Fixes #284

src/app/shared/language-selector/language-selector.component.ts

@@ -0,0 +1,59 @@
+/** Angular Imports */
+import { Component, OnInit } from '@angular/core';
+import { FormControl } from '@angular/forms';
+
+/** Custom Services */
+import { I18nService } from 'app/core';
+
+/**
+ * Language selector component.
+ *
+ * TODO: Decision to be taken on using ngx-translate or angular-internationalization
+ *       to provide language support in the application.
+ */
+@Component({
+  selector: 'mifosx-language-selector',
+  templateUrl: './language-selector.component.html',
+  styleUrls: ['./language-selector.component.scss']
+})
+export class LanguageSelectorComponent implements OnInit {
+
+  /** Language selector form control. */
+  languageSelector = new FormControl();
+
+  /**
+   * Sets the language of the application in the selector on initial setup.
+   * @param {I18nService} i18nService Internationalization Service.
+   */
+  constructor(private i18nService: I18nService) {
+    this.languageSelector.setValue(this.currentLanguage);
+  }
+
+  ngOnInit() {
+  }
+
+  /**
+   * Sets a new language to be used by the application.
+   * @param {string} language New language.
+   */
+  setLanguage(language: string) {
+    this.i18nService.language = language;
+  }
+
+  /**
+   * Returns the current language used by the application.
+   * @returns {string} Current language.
+   */
+  get currentLanguage(): string {
+    return this.i18nService.language;
+  }
+
+  /**
+   * Returns all the languages supported by the application.
+   * @return {string[]} Supported languages.
+   */
+  get languages(): string[] {
+    return this.i18nService.supportedLanguages;
+  }
+
+}