Bug 17597: Outdated translation credits

Bug 17597: Outdated translation credits

Updated translation credits for the Greek language.

Signed-off-by: Andreas Roussos <arouss1980@gmail.com>
Works as expected, hyperlink to openhub tested OK.
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>

Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
(cherry picked from commit 446142cd2ba6b9ace602d918e5ef83b0b0ccfa6a)
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
(cherry picked from commit 5c04130720d0497f78aad2c1850f858637355e0b)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>