refactor the parsing into the module change the mscan format string to siplify the parsing, and refactor the parsing code into the module for reuse. pe is an exception in that it doesn't care about the format string, it just need to decide if the current line starts a new thread or not, that's why it doesn't use the newly introduced `parse'. The new format simplifies pe too though.

pe: be less chatty

pledge and unveil the scripts

parallelize exporting mexp is the slowest part of the pipeline. Try to speed it up by paralellizing it. this adds a `pe' scripts that sits in front on N mexp childs and dispatch threads to them, while still outputting the unchanged lines for mkindex. Unscientific testing has shown that this effectively reduces the time for a full export, even if not linearly. (4 jobs cut the time in half, 8 jobs was just barely faster)