Miaschiev: Fix some issues browsing for install & save paths
Miaschiev: Print exceptions to stderr as well as the status bar
Miaschiev: Log stdout/stderr to miaschiev.log running under bbfreeze
Miaschiev: Fix regression decoding exposure map

This was caused by changes to the data_raw type for formatting raw types
in Miasmod - Miaschiev was using the formatted version rather than
accessing the raw data directly.
miasmap: Don't die if Map_FilledIn.jpg hasn't been extracted

Eventually I should extract and decode it from main.rs5 directly, but
for now just ignore it if it doesn't exist.
markers.py: Update code to use Rs5ChunkedFileDecoder
Miaschiev: Plot known head statues on map