added some eclipse related  files to gitignore
eliminated warnings

Added //$CASES-OMITTED$ tag comment to eliminate warnings in Eclipse,
e.g., "The enum constant SAME_INDIVIDUAL needs a corresponding case
label in this enum switch on InferenceType".
cleaned up unused imports warnings
added generated serial version ids
Upgrade to OWL API 3.5.0.  Fixes #2.
Added YAML file for Travis CI.