API 0.5 -> 0.6 DB MIGRATION CODE
		   ================================

PLEASE NOTE: THIS IS A VERY GOOD EXAMPLE OF WHY IT IS *NOT* A GOOD
IDEA TO "SCRIPT" IN C++!

Overview
========

There are two major parts of the code: copy_table and changeset_synth.

Copy table copies a set of tables from a MySQL server (possibly
remote) to a PostgreSQL server (possibly remote) while changing the
schema to match that of the 0.6 database. This involves some fairly
nasty hacks with re-ordering tables, keeping track of versions,
etc... Needless to say, it isn't pretty. You have been warned.

Changeset synth takes the data tables and generates changesets
according to the changeset rules (idle time 1 hour, no changeset lasts
longer than 24 hours, no changeset contains more than 50,000 changes)
and inserts them into the changesets table. To run this you need to
add a column to nodes, ways and relations called "new_changeset_id",
as the existing "changeset_id" column actually contains the user
id. Its a good idea to build some indexes too. After the synth is done
it is safe to drop changeset_id, rename new_changeset_id to
changeset_id and then re-create the indexes and FK constraints. This
might seem like a weird way to do it, but it was faster than
overwriting the existing column.

Disclaimer
==========

This isn't a late April Fool - you are advised to run screaming from
this code. If any code gets in contact with your eyes or skin, or if
any is ingested, seek medical attention IMMEDIATELY.

And all the rest of that stuff about no warranties, etc... Seriously,
this code could quite easily break your computer, burn down your house
and steal your car/bike/$FAVOURITE_POSSESSION.