* Api: Merge placeholder that checks for EMPTY {{IF fieldname~EMPTY~True text~False text}}

EMPTY check was already there, just adding it explicitly into the placeholder list

api/lang/egw_de.lang

@@ -260,6 +260,7 @@ change owner	common	de	Eigentümer ändern
 changed	common	de	Geändert
 charset	common	de	UTF-8
 check all	common	de	Alle auswählen
+check for empty values in if statements.  example {{if url~empty~~website:}} - if url is not empty, writes "website:"	common	de	Sie können auch auf EMPTY prüfen in If-Abfragen. Beispiel {{IF url~EMPTY~~Webseite: }}{{IF url~EMPTY~~url}} - fügt Webseite & URL ein, falls das Feld url nicht leer ist.
 check if content should only be displayed but not altered (the content is not send back then!)	common	de	abhaken wenn der Inhalt nur angezeigt aber nicht geändert werden soll (der Inhalt wird dann nicht zurückgesendet!)
 check if field has to be filled by user	common	de	abhaken wenn das Eingabefeld vom Benutzer zwingend ausgefüllt werden muss
 check installation	common	de	Installation überprüfen

api/lang/egw_en.lang

@@ -260,6 +260,7 @@ change owner	common	en	Change Owner
 changed	common	en	Changed
 charset	common	en	utf-8
 check all	common	en	Check all
+check for empty values in if statements.  example {{if url~empty~~website:}} - if url is not empty, writes "website:"	common	en	Check for empty values in IF statements.  Example {{IF url~EMPTY~~Website:}} - If url is not empty, writes "Website:"
 check if content should only be displayed but not altered (the content is not send back then!)	common	en	Should content be displayed only, but not altered.
 check if field has to be filled by user	common	en	Check if field has to be filled by user
 check installation	common	en	Check installation

api/src/Storage/Merge.php

@@ -2994,6 +2994,7 @@ abstract class Merge
 
 			// Commands
 			'IF fieldname'                  => lang('Example {{IF n_prefix~Mr~Hello Mr.~Hello Ms.}} - search the field "n_prefix", for "Mr", if found, write Hello Mr., else write Hello Ms.'),
+			'IF fieldname~EMPTY~True~False' => lang('Check for empty values in IF statements.  Example {{IF url~EMPTY~~Website:}} - If url is not empty, writes "Website:"'),
 			'NELF'                          => lang('Example {{NELF role}} - if field role is not empty, you will get a new line with the value of field role'),
 			'NENVLF'                        => lang('Example {{NENVLF role}} - if field role is not empty, set a LF without any value of the field'),
 			'LETTERPREFIX'                  => lang('Example {{LETTERPREFIX}} - Gives a letter prefix without double spaces, if the title is emty for  example'),