Fix for issue #58

[OdeyFox]

Fix for issue #58

• added functionality to load image from URL using Picasso.
• added functionality to change "title text color", "description text color", "title text style", "description text style", "title text size", "description text size".
• added TextStyle.java Enum.
• added internet permission to the fragment example.
• added Picasso dependency.

Usage

    PaperOnboardingPage scr1 = new PaperOnboardingPage("Hotels", "All hotels and hostels are sorted by hospitality rating",
                Color.parseColor("#678FB4"), R.drawable.hotels, R.drawable.key);

        scr1.setImageUrl("https://en.wikipedia.org/wiki/Pikachu#/media/File:Pok%C3%A9mon_Pikachu_art.png");
        scr1.setImageWidth(200);
        scr1.setImageHeight(100);
        scr1.setTitleTextColor(Color.parseColor("#FFFFFF"));
        scr1.setDescriptionTextColor(Color.parseColor("#FFFFFF"));
        scr1.setTitleTextSize(50);
        scr1.setDescriptionTextSize(30);
        scr1.setTitleTextStyle(TextStyle.BOLD_ITALIC);
        scr1.setDescriptionTextStyle(TextStyle.ITALIC);