Change file path to abstract representation.

The actual file passed is an implementation detail and using a real example would only serve to clutter showcasing the actual Picasso API.

We also don't want to give users the wrong idea in thinking that we support loading animated GIFs. Or humor.
Merge pull request #381 from square/jw/are-you-effing-serious

Change file path to abstract representation.
Use icon for sample app, use target 19.
Merge pull request #382 from square/dimitris/icons

Use icon for sample app, use target 19.
Add download stats.
Merge pull request #385 from square/dimitris/download-stats

Add download stats.
Create Options only when needed

Create `BitmapFactory.Options` only when resizing or giving a custom `Bitmap.Config`
`createBitmapOptions` will translate given `Request` to `BitmapFactory.Options`
Introduce `requiresInSampleSize` to determinate if computation of sample size is required
Added suggested chchchanges
Fix TargetActionTest.
Remove spaces, reformat JavaDoc
Merge pull request #387 from square/dimitris/fix-tst

Fix TargetActionTest.
Merge pull request #386 from eveliotc/no-options-no-cry

Create Options only when needed
If custom transformation fails, do not invoke stats.
Merge pull request #392 from square/dimitris/null-fix

If custom transformation fails, do not invoke stats.
Clarify documentation on config to note it's a prefered value.
Merge pull request #393 from square/jw/doc-clarification

Clarify documentation on config to note it's a prefered value.
Add support to load into remote views.