Convert some notes.xml files from latin-1 to utf-8

In the master branch, the encoding for most xml files have been
changed from latin-1 to utf-8. The problem is, that the corresponding
files in the maint branch still are encoded in latin-1, and that
a merge from maint to master may bring in characters encoded in latin-1
into a notes.xml file declared to be in utf-8.

To fix the problem once and for all (for the files involved), we'll
need to re-encode the files files utf-8 in maint, and then merge to
master.

Noticed-by: Magnus Henoch