Move to later dependencies

Move to later dependencies, update related code. Might break your code after update in part of setting up the admobadapter's objects since interface was changed a bit

Use banners support instead of deprecated express ads

The support of express ads has been dropped, please use banners instead (see details).

build wrappers via Builder pattern. setup VideoOptions.

1. add Video Options to ExpressAdPreset
2. a lot of refactoring. Adapter wrappers should be created via its' Builder.
3. bump platform and build tools to 26
4. fixes

advanced wrapping ads

Extract separate methods for both recycling of ads and adding it to the wrapper. You're able to override it with your custom implementation. See wiki https://github.com/clockbyte/admobadapter/wiki/Cookbook#in-case-you-want-to-wrap-your-ad-blocks-into-a-viewgroup-cardview-framelayout-etc and sampleapp for instance

a recycling of express ads was handled

• migrate to gradle 2.3.1 and bump all dependencies to latest available
• NOW admobadapter REQUIRES MIN SDK 14 due to a migration to the 10.2.x google services
• handles itself a recycling of ads in both ListView and RecyclingView. So ads should be different all over the list (besides a case when there's not enough ads in Admob Server).
  Side effects:
• less flexibility in overriding a wrapping view for Native Express Ads. You only inflate your custom wrapping view and return it to the library. Lib adds ad into wrapping view itself. Possibly will be improved in future.

a fix for negative fetched count

Could be reproduced via ListView and Express ads when there's no internet connection. Fixed thanks to @d-kostadinov.

A couple of bugfixes

a fix for #53
a fix for #49
Bump build tools version, firebase-ads and support libs versions to the latest.

use multiple unit ids! wrap the ad into your view!

@mourjan has provided multiple unit ids/ AdSize (named as ExpressAsPresets)
@lujop has implemented wrapping of ad views with a custom GroupView.
fix minor bugs, including a hide or duplicate of the source items with an incorrect unit id.
updated: build tools, some references, gradle plugin
update examples in sampleapp
minor changes

no flickering, no empty spaces!

• hide empty spaces while ads are loading
• subscribe to all "items changed" events of the underlying adapter in RecyclerView adapter wrappers.
• much refactoring. could require changes in your code! I'm going to publish to Maven central, I'll try to support backward then (by marking methods with @deprecated and so on).
• much optimization (SparseArray instead of HashMap, using postDelayed fetch to prevent a high-load of server et c)
• a fix for a duplicating of ad blocks when fetch it
• prefetching of ads was implemented in express adapters
• now you can inject your custom layout id and binding behavior to the wrappers by passing NativeAdLayoutContext objects into methods setContentAdsLayoutContext(...) and setInstallAdsLayoutContext(...)
• also you can set which type of advanced ads a wrapper should publish
• you are able now to inject all adapters that extended the RecyclerView.Adapter/ BaseAdapter to AdmobAdapter wrappers
• Merge pull request #19 from kimbeejay/master: RecyclerView.ViewHolder was refactored
• AdmobFetcherExpress methods were synced

custom indices logic

*WHATS NEW *

1. Now you are able to inject your own indices logic to adapter wrapper. Just inherit from AdmobAdapterCalculator and pass your implementation to the method adapterWrapper.setAdapterCalculator(...).
2. Ads express size issue was fixed, now you should set it from code (see Recipe 3 in our Cookbook).
3. An ability to set custom index of the first ad block was implemented
4. the method setTestDeviceId() is marked as deprecated, please use addTestDeviceId() instead