osm2bbd: protect from newlines or tabs in 'name' components

osm data may contain embedded newlines like

    <tag k="wikipedia" v="cs: Evangelicky Kristuv kostel&#10;(Ostrava)"/>

Now all newlines and tabs are replaced into spaces.

With a test case in osm2bbd.t. Additionally osm2bbd.t has a new --keep
option for easier debugging.
data update (mainly updates around Murellenschlucht and Olympiapark)
data update (Mergenthalerring)