gnucash-docs maint: EEC became EU decades ago, but we had still references

[Frank H.Ellenberger]

Updated	 via  https://github.com/Gnucash/gnucash-docs/commit/1cc6aa97 (commit)
	from  https://github.com/Gnucash/gnucash-docs/commit/119c44b7 (commit)



commit 1cc6aa97136d659cb51a05b36808b088f9d14863
Author: Frank H. Ellenberger <frank.h.ellenberger at gmail.com>
Date:   Fri Apr 23 18:55:27 2021 +0200

    EEC became EU decades ago, but we had still references



Summary of changes:
 guide/C/appendixc.xml      |    2 +-
 guide/de/appendixc.xml     |   10 +-
 guide/it/gnucash-guide.xml |   10 +-
 guide/it/it.po             | 2632 +-------------------------------------------
 guide/ja/appendixc.xml     |    8 +-
 guide/pt/appendixc.xml     |   10 +-
 guide/ru/appendixc.xml     |   10 +-
 7 files changed, 30 insertions(+), 2652 deletions(-)