contrib/lisp/org-contacts.el: Add a feature, which can ignore emails or phones with property

* contrib/lisp/org-contacts.el (org-contacts-ignore-property): New variable.
(org-contacts-remove-ignored-property-values): New function, which
remove all ignore-list's elements from list.
(org-contacts-complete-name): When completing, ignore the
values which has been included into the ignore property.
(org-contacts-vcard-format): Don't export the values which has
been included into the ignore property.

If emails or phones is included into the ignore property, they will
not show in complete buffer. When the contact is exported to vcard,
they will be ignored too.

contrib/lisp/org-contacts.el

@@ -86,6 +86,11 @@ When set to nil, all your Org files will be used."
   :type 'string
   :group 'org-contacts)
 
+(defcustom org-contacts-ignore-property "IGNORE"
+  "Name of the property,  which values will be ignored when complete or export to vcard."
+  :type 'string
+  :group 'org-contacts)
+
 
 (defcustom org-contacts-birthday-format "Birthday: %l (%Y)"
   "Format of the anniversary agenda entry.
@@ -476,6 +481,16 @@ A group FOO is composed of contacts with the tag FOO."
 		(completion-table-case-fold completion-list
 					    (not org-contacts-completion-ignore-case))))))))
 
+
+(defun org-contacts-remove-ignored-property-values (ignore-list list)
+  "Remove all ignore-list's elements from list and you can use
+   regular expressions in the ignore list."
+    (remove-if (lambda (el)
+               (find-if (lambda (x)
+                          (string-match-p x el))
+                        ignore-list))
+             list))
+
 (defun org-contacts-complete-name (start end string)
   "Complete text at START with a user name and email."
   (let* ((completion-ignore-case org-contacts-completion-ignore-case)
@@ -484,10 +499,17 @@ A group FOO is composed of contacts with the tag FOO."
 		;; The contact name is always the car of the assoc-list
 		;; returned by `org-contacts-filter'.
 		for contact-name = (car contact)
+
+		;; Build the list of the email addresses which has
+		;; been expired
+		for ignore-list = (org-contacts-split-property (or
+								(cdr (assoc-string org-contacts-ignore-property
+										   (caddr contact))) ""))
 		;; Build the list of the user email addresses.
-		for email-list = (org-contacts-split-property (or
-						(cdr (assoc-string org-contacts-email-property
-								   (caddr contact))) ""))
+		for email-list = (org-contacts-remove-ignored-property-values ignore-list
+									      (org-contacts-split-property (or
+													    (cdr (assoc-string org-contacts-email-property
+															       (caddr contact))) "")))
 		;; If the user has email addresses…
 		if email-list
 		;; … append a list of USER <EMAIL>.
@@ -869,15 +891,17 @@ to do our best."
 	 (n (org-contacts-vcard-encode-name name))
 	 (email (cdr (assoc-string org-contacts-email-property properties)))
 	 (tel  (cdr (assoc-string org-contacts-tel-property properties)))
+	 (ignore  (cdr (assoc-string org-contacts-ignore-property properties)))
 	 (note (cdr (assoc-string org-contacts-note-property properties)))
 	 (bday (org-contacts-vcard-escape (cdr (assoc-string org-contacts-birthday-property properties))))
 	 (addr (cdr (assoc-string org-contacts-address-property properties)))
 	 (nick (org-contacts-vcard-escape (cdr (assoc-string org-contacts-nickname-property properties))))
 	 (head (format "BEGIN:VCARD\nVERSION:3.0\nN:%s\nFN:%s\n" n name))
+	 (ignore-list (when ignore (setq ignore-list (org-contacts-split-property ignore))))
 	 emails-list result phones-list)
     (concat head
 	    (when email (progn
-			  (setq emails-list (org-contacts-split-property email))
+			  (setq emails-list (org-contacts-remove-ignored-property-values ignore-list (org-contacts-split-property email)))
 			  (setq result "")
 			  (while emails-list
 			    (setq result (concat result  "EMAIL:" (org-contacts-strip-link (car emails-list)) "\n"))
@@ -886,7 +910,7 @@ to do our best."
 	    (when addr
 	      (format "ADR:;;%s\n" (replace-regexp-in-string "\\, ?" ";" addr)))
 	    (when tel (progn
-			(setq phones-list (org-contacts-split-property tel))
+			(setq phones-list (org-contacts-remove-ignored-property-values ignore-list (org-contacts-split-property tel)))
 			(setq result "")
 			(while phones-list
 			  (setq result (concat result  "TEL:" (org-contacts-strip-link (car phones-list)) "\n"))