WL#4642: Greek locale for DAYNAME, MONTHNAME, DATE_FORMAT

If @@lc_time_names='el_GR', DAYNAME() and MONTHNAME() and
DATE_FORMAT() functions should produce appropriate Greek
results for day abbreviation, day, hours am/pm,
month abbreviations, and months.

This task is a part of Sun Globalization Requirements.

Functions DAYNAME, MONTHNAME, DATE_FORMAT currently do not support
Greek locale (Tier 2).

http://dev.mysql.com/doc/refman/5.0/en/locale-support.html

This task will add el_GR locale with appropriate month/day names.

Days
----

day abbreviation: (abday):

Sunday    = Κυρ "";
Monday    = Δευ "";
Tuesday   = Τρί "";
Wednesday = Τετ "";
Thursday  = Πέμ ""
Friday    = Παρ "";
Saturday  = Σάβ "";

day:

Sunday    = "Κυριακή"   = ""
Monday    = "Δευτέρα"   = ""
Tuesday   = "Τρίτη"     = ""
Wednesday = "Τετάρτη"   = ""
Thursday  = "Πέμπτη"    = ""
Friday    = "Παρασκευή" =
""
Saturday  = "Σάββατο"   = ""

Hours
-----

am= "πμ" = ""
pm= "μμ" = ""

Months
------

month abbreviation: (abmon):

Jan = 
Feb = 
Mar = 
Apr = 
May = 
Jun = 
Jul = 
Aug = 
Sep = 
Oct = 
Nov = 
Dec = 

month: (mon):














month (using text notation):
January   = "Ιανουάριος"
February  = "Φεβρουάριος"
March     = "Μάρτιος"
April     = "Απρίλιος"
May       = "Μάιος"
June      = "Ιούνιος"
July      = "Ιούλιος"
August    = "Αύγουστος"
September = "Σεπτέμβριος"
October   = "Οκτώβριος"
November  = "Νοέμβριος"
December  = "Δεκέμβριος"

Nynorsk
-------

During discussion about this WL and WL#751 it appeared
that we're missing the Norwegian Nynorsk locale.
It was decided that Nynorsk will be a separate worklog task,
WL#4814 Norwegian Nynorsk locale for DAYNAME, MONTHNAME, DATE_FORMAT

Authority
---------

None. See comment on BUG#39092 regarding ΕΛΟΤ.

On Linux distributions one can find a file named /usr/share/i18n/locales/el_GR
but we do not follow it. For example our day abbreviations are as in Vista.

References
----------

BUG#39092 Greek LOCALE support (feature request)

dev-private email thread "WL#4642 Greek locale for DAYNAME, MONTHNAME,
DATE_FORMAT, some questions" starting at
[mysql intranet]/secure/mailarchive/mail.php?folder=4&mail=26821