Update gradle, android plugin, support library,...

* Gradle (wrapper) updated from 1.11 to 1.12
* Gradle Android plugin updated from 0.9.+ to 0.11.+
* Support Library updated from 18.0.+ to 19.1.0
* Build Tools updated from 19 to 19.1.0
* NEW plugin android-sdk-manager, will download new build tools, SDK
  versions,... as declared in `build.gradle` on demand
* Checkstyle is now part of the `build` lifecycle
* `gradle.properties` file added, includes the daemon and parallel
  execution. AFAIK this is not honoured by AS as it has its own settings
  and uses the daemon by default, but it speeds up commandline builds
  (not clean builds but incremental ones). Benchmarks below.
* Had to change the classpath variable of the checkstyle task because
  otherwise it wouldn't compile for me. Works on my machine doing `gw
  checkstyle`.

Benchmarks:
Not parallel:
```
gw clean:
Total time: 13.921 secs

gw assDe:
Total time: 1 mins 32.123 secs

gw clean:
Total time: 12.841 secs

gw assDe:
Total time: 1 mins 19.26 secs

gw clean:
Total time: 13.316 secs

gw assDe:
Total time: 1 mins 26.894 secs

gw assDe:
Total time: 12.774 secs

gw assDe:
Total time: 13.149 secs
```

Parallel + Daemon
```
gw clean:
Total time: 12.18 secs

gw assDe:
Total time: 1 mins 10.839 secs

gw clean:
Total time: 4.368 secs

gw assDe:
Total time: 1 mins 27.029 secs

gw clean:
Total time: 4.055 secs

gw assDe:
Total time: 1 mins 6.845 secs

gw assDe:
Total time: 5.357 secs

gw assDe:
Total time: 3.644 secs
```

Results:
`gw clean build` is a bit faster, but not by a lot, `clean` is a
lot faster, as are subsequent incremental builds (note: not really an
incremental build in this case, because the source wasn't modified at
all). I use these settings at work on the console and did not encounter
any problems so far. For parallel builds in Android Studio, see the
compiler settings there.

Notes:
I use `gw` instead of `./gradlew` or `../gradlew` (see [this][1] post
by Jakewharton for more info) as well as [task name abbreviation][2] in
case you wonder what exactly I am doing in the benchmarks, `assDe` = `assembleDebug`.

[1]: https://plus.google.com/+JakeWharton/posts/hPkaEwza6HG
[2]: http://www.gradle.org/docs/current/userguide/userguide_single.html#N107F0

* Fix excludes for checkstyle gradle task

* Adapt to new directory layout of build/

See [this G+ post][1] (down in the comments, search for 'intermediates')
for more details.

[1]: https://plus.google.com/+AndroidDevelopers/posts/Tzof6zatrJW

* ignore new lint checks
Merge pull request #999 from Catrobat/ar/updates

Update gradle, android plugin, support library,...
Update README.md

Adding link to new setup of the working environment
Physic-Integration, create packages and Datatypes,

first step, not yet used
physic integration- modify, actions, new classes

add: physicactions; physicfactory modify: Sprite, Project
add bricks, layouts, res
StageListener, PreStageActivity, Factory

PhysicWorld step.....
move ExtendedActionFunctions

move remaining ExtendedActionFunctions to ActionFactory
add PhysicActionMultiStepExtension + modifications
file
add requiered png's for physic standartproject
PhysicsLook
physicObject
Fix PhysicsLook positioning bug.

Add x/y-getters for PhysicsLook.
Update pinball standard project rotation values.
Replace Sprite resources member with query.
Disable nonrelevant render settings.
rm PhysicActions, PhysicFactoryFunctions .....

remove unused PhysicActions
remove unused Functions in PhysicFactory
remove default BoundaryBox
rm physichock,TemporalAction,IfOnEdgeBounceAction

no need for hocks anymore -> physiclook
let the look know about the begin and end of a TemporalAction
Override-> createIfOnEdgeBounceAction [ActionPhysicsFactory]
collision - step
fixGlideTo and refactor BitMask for collision
Testcase-Fixes Part one
Testcase Compile Errors fixed