bump Klee version

bump LLVM version

bump Hiredis version

install the Hiredis static library and include files by hand; do not build the
shared lib
Merge pull request #69 from regehr/bump-klee

bump Klee version, LLVM version, Hiredis version, build and install only the static hiredis lib
Merge branch 'master' into split
make ReplacementKind an enum class

in printReplacementRHS and getRHSString, assert that the Inst is a
Const