ElementTree is not available by default. (it is in pyexpat, which is
a non-default module.)
since ElementTree is only used by the Updater code, and this code is
not designed to run on the NanoNote (it is only run as part of the
build process), move the import statement inside the Updater in the
hopes that the user on the NanoNote never has to deal with it.
In the future I will make pyexpat a default module for the Lojban
config, but this change will still see a performance gain in the
most typical use case for makfa.
I originally choose /var/lib/... because makfa.dump can be updated by
the makfa program. /usr/share/... is for read-only data, which this
most certainly is not.
The best solution for this problem would be to have some kind of
/ovelay/var/... directory that is copied at boot to /var/... This
would allow files that need to be persistent in /var/... to be so,
but would permit the flexibility currently seen for I/O heavy uses
of /var/...
Ater a discussion with xiangfu, we decided that modifying the
base-package to support an overlay on /var is too much work to do
right now, and that we would use /usr/share/... for the time being.