Feature list preloader support multiple target sizes

rename preloadItem(List<T> items, int position, boolean isIncreasing) to preloadAdapterPosition(List<T> items, int position, boolean isIncreasing)

Fixes #270.

Split interface to provide the size seperatly. Change interface on `PreloadModelProvider` so preload items will requested one by one.
 - introduce new interface `PreloadSizeProvider`
 - change `PreloadModelProvider` preload items will requested one by one.
 - adapt Tests
 - adapt Samples
 - add two sample implementation for `PreloadSizeProvider`
      - `FixPreloadSizeProvider` to provide a size with a fixed width and height
      - `ViewPreloadSizeProvider` provide a size request from a given view using a `OnPreDrawListener`

In your examples the ListAdapter and the final ListPreloader are
strongly connected. Using an Interface will remove this strong
connection.

Using an interface that an Adapter can implement has the following
advantages:
1. the dimensions don´t must be passed to the ListPreloader while the Adapter has the first access to the dimensions of the ImageView
2. you don´t have to pass the items to the ListPreloader, while the
Adapter already has the newest set of items (e.g.: CursorAdapter)
3. in most cases the ListAdapter already has an RequestBuilder, so
you don´t have to pass them twice
4. you get rid of an extra class (ListPrelaoder) you have to implement

Ability to load a bitmap into an ImageView of a Widget using
RemoteViews.

Example of usage on the following gist
https://gist.github.com/pavlospt/00242d5102ac8f76e169

Fixes #258

Fixes #244

Fixes #234

Related to #233.

resetStaticState was removed here:
https://github.com/robolectric/robolectric/pull/1364

Fixes #225.

This reverts commit deef4ae2.
Fixes #231.
Reopens #225.

Depending on the order tests are run in, this
seems to be able to cause errors.