Calculate matrix profile in debug

Returns profile reduction ratio in debug mode
Fixed solution time for power method
new functions: parallel_map with a unified API that allows multiprocessing and ipython.parallel implementations to be swappable
fixed spelling typo
remove stray line
All solvers return residual norm
use AsyncResult.wait(...) to consume less cpu resources while waiting for child processes
unified progress_bar argument
fixed spelling error
Merge branch 'master' into feature-unified-parallel-map
code style fixes
restore the old text based progress bar as default, keep the new text based progress bar as EnhancedTextProgressBar
explicitly finalize progress bar
added unit tests for parallel_map
rename module parfor to parallel
fix import error after parfor -> parallel rename
fixed bug in hadamark reported by @ajgpitch. Closes #257
fixed import of renamed module
fix issue with default number of processing in parallel code being 1 rather than the number of available cores
use parallel_map in parfor in ipynbtools module