## 0.2.1

### New Features

* The `DataFlow::StateConfigSig` signature module has gained default implementations for `isBarrier/2` and `isAdditionalFlowStep/4`. 
  Hence it is no longer needed to provide `none()` implementations of these predicates if they are not needed.

### Minor Analysis Improvements

* Data flow configurations can now include a predicate `neverSkip(Node node)`
  in order to ensure inclusion of certain nodes in the path explanations. The
  predicate defaults to the end-points of the additional flow steps provided in
  the configuration, which means that such steps now always are visible by
  default in path explanations.
* The regular expression library now understands mode flags specified by `Regex` methods and the `NSRegularExpression` initializer.
* The regular expression library now understands mode flags specified at the beginning of a regular expression (for example `(?is)`).
* Added detail to the taint model for `URL`.
* Added new heuristics to `SensitiveExprs.qll`, enhancing detection from the library.