[f] support set show icon or not, add menu icon without icon

[luongvo]

This resolve #21

• Create builder method addItem(int id, @StringRes int title) and addItem(int id, String title) to add menu without drawable icon
• Create builder method setShowIcon(boolean showIcon) to enable or disable icon showing in menu item layout
• Update example and readme

[prscX]

Hi @rubensousa: Can you please review and merge this PR.

Thanks </ Pranav >

[rubensousa]

The PR should be submitted against dev instead of master. I'll try to push this myself to dev tomorrow since I can't do it today. Sorry for taking too long to respond to this :/

[prscX]

Thanks @rubensousa. Looking forward for a release.

Thanks, </ Pranav >

[luongvo]

@rubensousa @prscX just switched to dev instead of master, also resolved conflicts too, please review it. Thanks 🚀

[rubensousa]

Looks great to me, but I just have one question: why don't we just check if the icon exists inside the view holder? This way, we also allow showing items with icons mixed with ones that don't have icons. Or maybe both: checking if the flag is true and checking if the icon exists to toggle the imageview visibility. What do you think?

This would also cover: https://github.com/rubensousa/BottomSheetBuilder/pull/32

[eladgel]

Any news on this?