make node groups more modular
move node-specific DOT generation into node group files
separate file for python ast support
bugfixes, avoid writing out dot files
initial omp test
basic omp nodes and tests for codegen
don't print semicolons after OpenMP statements
force arguments to influence transformation only through program_config
implement runtime statistics
use ctree.dotgen instead of AstToDot
implement CtreeNode.insert_before so we can prepend stmts with omp pragmas
better error msg
load libiomp
only warn if omp runtime doesn't load
i confused tx and xf
use llvm.core's library loader
use standard dot generator
implement CtreeNode.insert_after
tests for replacement, and implement replacing within lists
try coverage