add scala nature and files

 - add kore module to the mvn build system, make kernel (and only kernel) dependent on kore
 - add Scala KORE classes
kernel depends on kore
Merge branch 'hotfix/rename-k-core-to-kernel' into feature/scala-module
refactor io in smt prelude
implemented [trusted] attribute for the ml prover
implemented basic AC-unification for BuiltinSet
evaluated the LHS of a rule as well
minor cleanup
Revert "evaluated the LHS of a rule as well"

This reverts commit e3dca7885d4b3e9927597dd6c55567d709c9223d.
added comment
Merge pull request #1137 from yilongli/prove-cil-list-reverse-2

patch in order to prove the entire cil list reverse example
Merge pull request #1135 from dwightguth/smtprelude

refactor io in smt prelude
Merge pull request #1131 from cos/feature/scala-module

add Scala KORE inner classes
patch in order to prove cil bst find example
evict stuff from kparser cache
refactor ktest to run krun immediately following kompile
make initial config obtained only once via provider instead of singleton
change krun to normalize fresh variables in output
addressed Andrei's comment
Merge pull request #1138 from yilongli/prove-cil-bst-find

patch in order to prove cil bst find example