Updated documentation

README.md

@@ -5,6 +5,7 @@ a small library to send a email in background withou user interaction
                 .withUsername("username@gmail.com")
                 .withPassword("password12345")
                 .withMailto("toemail@gmail.com")
+                .withType(BackgroundMail.TYPE_PLAIN)
                 .withSubject("this is the subject")
                 .withBody("this is the body")
                 .withOnSuccessCallback(new BackgroundMail.OnSuccessCallback() {

gmailbackgroundlibrary/src/main/java/com/creativityapps/gmailbackgroundlibrary/BackgroundMail.java

@@ -37,6 +37,9 @@ public class BackgroundMail {
     private OnSuccessCallback onSuccessCallback;
     private OnFailCallback onFailCallback;
 
+    public final static String TYPE_PLAIN = "text/plain";
+    public final static String TYPE_HTML = "text/html";
+
     public interface OnSuccessCallback {
         void onSuccess();
     }
@@ -323,7 +326,7 @@ public static final class Builder {
         private String mailto;
         private String subject;
         private String body;
-        private String type = "text/plain";
+        private String type = BackgroundMail.TYPE_PLAIN;
         private ArrayList<String> attachments = new ArrayList<>();
         private String sendingMessage;
         private String sendingMessageSuccess;
@@ -379,6 +382,7 @@ public Builder withSubject(@StringRes int subjectRes) {
             return this;
         }
 
+        //set email mime type
         public Builder withType(@NonNull String type) {
             this.type = type;
             return this;