Attempts to avoid the pre-fetch step when building
by only pre-allocating the measurement tables
and not all of the strings. Therefore writing
the table will take longer, but without the
costly pre-fetch step.
In theory writing could be parallelized for some formats also.

This should also move file creation closer to
writing, which should help avoid the situation
possible at the moment where we overwrite a
file and then crash before writing a single byte to it
without throwing an exception (if createMeasurementTable fails).