* VariableAction stores the real name and the variable may be null.
* VariableVisitor entrypoint must be #startVisit().

Updated variable_pattern_regex to match VariableActions regarding object fields accessed in different ways

Fix github#44 (-i flag misbehaving)

Closes #44

See merge request !54

Replaced by linear lookup.

Fixes #44

Interprocedural DynamicTypeResolver

Closes #45

See merge request !53

* Closes #45
* Alters VariableAction to take Expression as argument (either NameExpr or FieldAccessExpr).
* Expands the CallGraph API
* Fixes bug where movable definitions were created incorrectly.
* Now accepting FieldAccessExpr completely.

Polymorphic call graph

See merge request !51

* Fix for SlicerTest: use StaticTypeSolver.
* CallGraph#getCallTarget is now plural.
* CallConnectors edited to iterate over targets.

# Conflicts:
#	sdg-core/src/main/java/es/upv/mist/slicing/graphs/ClassGraph.java
#	sdg-core/src/main/java/es/upv/mist/slicing/nodes/VariableVisitor.java
#	sdg-core/src/main/java/es/upv/mist/slicing/utils/ASTUtils.java

Resolve "Use a specific kind of set with JavaParser nodes"

Closes #43

See merge request !50

Expected removal of repeated statements that were incorrectly included in the slice by SlicePruneVisitor without being marked as such by the algorithm.