ActionDB 0.6.0

This release mostly contains internal changes and a suffix array Matcher implementation.

• suffix tree refactoring
• remove forgotten println! call
• refacor Parser by removing LengthCheckedParserBase struct
• add HasLengthConstraint trait
• remove Factory
• rename GenericFactory to PatternLoader
• rename Builder to MatcherBuilder
• rename drain_into to from_source
• add FromPatternSource trait
• add a suffix array based Matcher implementation
• use travis-cargo in Travis
• test on stable, beta, previous stable rustc releases
• update clap to 1.5