Reproducing list of apps to share in Lolipop

[doyonghoon]

This pull request will resolve the issue #26.
The changes may not be clear, this is just a prototype that focuses on reproducing list of apps to share in Lolipop. The options to enable it in Dialog Plus Sample are that checking List Holder, Show fixed header. After that, just click BOTTOM button.

Remaining tasks

• alter global variables as a plain name without m prefix.
• support backwards compatibility, currently only runnable on api >= 21.
• give an intuitive name to the DimmedListHolder, the meaning of its name is vague.
• add comments on related changes that play a pivotal role in presenting list of apps to share like Lolipop.

[doyonghoon]

@orhanobut mind that the feature is not completed yet, but this is just a prototype. I will add comments on every changes to let you understand more clearly. Also, I will update what tasks are remaining to complete this feature later. thanks.

[orhanobut]

@doyonghoon sure, we can go through PR together

[yekmer]

Convention for library is not using m prefix for variable names. i.e. writing maxWidth instead of mMaxWidth makes sense. All fields should be renamed in this class then

[orhanobut]

@doyonghoon I haven't checked the code but did you find any solution for the getNestedScrollAxes()? Apparently this feature will be very good

[doyonghoon]

@orhanobut no, unfortunately there's no alternative way found to perform the same method that getNestedScrollAxes() does..

[orhanobut]

no longer valid.