Added changes to readme.md + comments. (commons-app#5230)

* Update README.md

* Update LatLng.java

* Update LoginActivity.java

* Updated LoginActivity.java to feature javadoc syntax

Author: tpettwa1

README.md

@@ -6,7 +6,7 @@
 
 The Wikimedia Commons Android app allows users to upload pictures from their Android phone/tablet to Wikimedia Commons. Download the app [here][1], or view our [website][2].
 
-Initially started by the Wikimedia Foundation, this app is now maintained by grantees and volunteers of the Wikimedia community. Anyone is welcome to improve it, just choose among the [open issues][3] and send us a pull request :-) 
+Initially started by the Wikimedia Foundation, this app is now maintained by grantees and volunteers of the Wikimedia community. Anyone is welcome to improve it, just choose among the [open issues][3] and send us a pull request! :-) 
 
 <a href="https://f-droid.org/repository/browse/?fdid=fr.free.nrw.commons" target="_blank">
 <img src="https://upload.wikimedia.org/wikipedia/commons/archive/9/96/20200131184248%21%22Get_it_on_F-droid%22_Badge.png" alt="Get it on F-Droid" height="90"/></a>
@@ -15,7 +15,7 @@ Initially started by the Wikimedia Foundation, this app is now maintained by gra
 
 ## Documentation
 
-We try to have an extensive documentation at our [documentation repository][4]:
+Our [documentation repository][4] contains extensive documentation for users, contributors, and developers alike:
 
 * [User Documentation][5]
 * [Contributor Documentation][6]

app/src/main/java/fr/free/nrw/commons/auth/LoginActivity.java

@@ -147,7 +147,11 @@ public void onCreate(Bundle savedInstanceState) {
             loginCredentials.setVisibility(View.GONE);
         }
     }
-
+    /** 
+     * Hides the keyboard if the user's focus is not on the password (hasFocus is false).
+     * @param view The keyboard
+     * @param hasFocus Set to true if the keyboard has focus
+     */
     @OnFocusChange(R.id.login_password)
     void onPasswordFocusChanged(View view, boolean hasFocus) {
         if (!hasFocus) {

app/src/main/java/fr/free/nrw/commons/location/LatLng.java

@@ -38,7 +38,10 @@ public LatLng(double latitude, double longitude, float accuracy) {
         this.latitude = Math.max(-90.0D, Math.min(90.0D, latitude));
         this.accuracy = accuracy;
     }
-
+    /**
+     * An alternate constructor for this class.
+     * @param in A parcelable which contains the latitude, longitude, and accuracy
+     */
     public LatLng(Parcel in) {
         latitude = in.readDouble();
         longitude = in.readDouble();