memory improvement: do not store implicit TOP values
bugfix: when propagating inside out into a caller that was not yet processed we need to create a summary edge starting at ZERO, not at the callee's flow fact!
Merge commit '987a7a4cd3a22d19845fd59885bfd25170798fe7' into develop
initial draft of BiDi Solver
more advances on BiDi Solver
changing initialization of analysis such that initialSeeds not is a mapping from units to initial data-flow facts at these units

this is a breaking change, but the class DefaultSeeds can be used to easily convert a set of units (old format) into a default map that should work for current clients

the change was implemented to permit subtypes of IFDSTabulationProblem to overwrite facts at seeds in a convenient way
Merge branch 'develop' into forks/java-fw-bw
updated initialSeeds to include source statement
made process* methods protected
extracting method submitInitialSeeds to allow submission without having to wait
added support for debug name
removed unused import
BiDiSolver: support for debug name and simultaneous submission of both analyses
finalized (?) logic for bidi solver
make "propagate" protected
removed superfluous type parameter from PathEdge
Merge branch 'develop' into forks/java-fw-bw

Conflicts:
	src/heros/solver/IDESolver.java
changed signature of "propagate" to include original call site for return and call flows

modified bidi solver to changed attached source statement on return
toString
don't forget to clear pause list un unpause