[simplified-mapred] Add simplified MapReduce job implementation with tests
Merge branch 'master' into simplified-mapred

Conflicts:
	src/main/java/pl/edu/agh/student/offlinedstream/Coordinates.java
	src/main/java/pl/edu/agh/student/offlinedstream/Grid.java
	src/main/java/pl/edu/agh/student/offlinedstream/OffDstream.java
	src/main/java/pl/edu/agh/student/offlinedstream/OffDstreamMapper.java
	src/main/java/pl/edu/agh/student/offlinedstream/OffDstreamReducer.java
Merge pull request #1 from jstypka/simplified-mapred

Simplified MapReduce job