Fixed `onNavigationItemSelected` was triggered 2 times when using `se…

…tupWithViewPager`

Add support for sdk 26.

Fixed: issue 34 35, the text gone when click quick.

Fixed: issue 28. getItemCount() return 0 when res not loaded.

Add style : unchecked first time.

Add setIconMarginTop. Remove setIconCenter.

Add new api.

Fix bug: custom typeface not work. Add new style : icon selector.

Add setTypeface.

Change minSdkVersion to 9.