Added standard ObservationTable and applied it to GenericLStar
Refactored GlobalSuffix feature and applied it to learning algorithms where applicable
Minor refactorings in ObservationTable interface & wrapper in generic lstar
Algorithm Features Refactoring WiP
Use new ObservationTable interface
Replace private helper method with Word.prefixes
Add JSR305 annotations (@Nullable, Nonnull)
(cherry picked from commit 7a09f53)
Use JSR305 annotations for BaselineLStar
Merge branch 'algorithm-features' of github.com:LearnLib/learnlib into algorithm-features
Merge branch 'develop' into algorithm-features

Conflicts:
	algorithms/dhc/pom.xml
	algorithms/lstar-baseline/pom.xml
	algorithms/lstar-generic/src/main/java/de/learnlib/algorithms/lstargeneric/table/ObservationTable.java
	pom.xml
Make basline ObservationTable less generic
Use single characters instead of strings
Merge branch 'algorithm-features' of git@github.com:LearnLib/learnlib.git into algorithm-features
Removed unnecessary unboxing
Suppress nonnull warning
Refactored and documented features module
Incorporated feature API refactorings into baseline LStar
Updated gitignore
Minor refactorings in ReuseTree
Merge pull request #14 from LearnLib/algorithm-features

Algorithm features