Moved extra keys into new object and remove search drink content and
layout

re: #7
Added state to drink class

re: #7
Minor tweaks to resolve the moving of intent keys etc.

Also some minor de-linting of main manifest

re: #7
Updates to results display.

re: #7
Updates to start getting the list of matching drinks

re: #7
Changed drink abv to a string

This avoids any issues with string formatting and proguard not keeping
`StringLike.toString()`

re: #7
Completed basic display of available drinks

re: #7
Added views for available beers, ciders and perries and simplified item
display.

I have also had to put a number of guards in to avoid null pointer
issues.

re: #7
Merge branch 'feature/AddDisplayOfFoundDrinks' into develop
Added support for file storage of festival data in main activity.

The data can now be downloaded and stored locally and then read when
required. 

re: #7
Added update data button

This will re-download the current festival data and re initialise the
model.

re: #7
Corrected reload logic to reload the festival model if the data was
reloaded.

re: #7
Added app icon

re: #7
Merge branch 'feature/StoreAndUpdateResults' into develop
Bump version to 0.2-SNAPSHOT