Update version and date for 2.3.

wiki/src/inc/stable_i386_date.html

-2016-03-18
+2016-04-26

wiki/src/inc/stable_i386_gpg_verify.html

-gpg --keyid-format 0xlong --verify tails-i386-2.2.1.iso.sig tails-i386-2.2.1.iso
+gpg --keyid-format 0xlong --verify tails-i386-2.3.iso.sig tails-i386-2.3.iso

wiki/src/inc/stable_i386_iso_sig_url.html

-https://tails.boum.org/torrents/files/tails-i386-2.2.1.iso.sig
+https://tails.boum.org/torrents/files/tails-i386-2.3.iso.sig

wiki/src/inc/stable_i386_iso_url.html

-http://dl.amnesia.boum.org/tails/stable/tails-i386-2.2.1/tails-i386-2.2.1.iso
+http://dl.amnesia.boum.org/tails/stable/tails-i386-2.3/tails-i386-2.3.iso

wiki/src/inc/stable_i386_release_notes.de.po

@@ -19,5 +19,5 @@ msgstr ""
 #.  Note for translators: make sure that the translation of this link
 #. integrates well with /doc/first_steps/upgrade. 
 #. type: Content of: outside any tag (error?)
-msgid "[[release notes|news/version_2.2.1]]"
-msgstr "[[Versionshinweise|news/version_2.2.1]]"
+msgid "[[release notes|news/version_2.3]]"
+msgstr "[[Versionshinweise|news/version_2.3]]"

wiki/src/inc/stable_i386_release_notes.fa.po

@@ -23,6 +23,6 @@ msgstr ""
 #. integrates well with /doc/first_steps/upgrade. 
 #. type: Content of: outside any tag (error?)
 #, fuzzy
-#| msgid "[[release notes|news/version_2.2.1]]"
-msgid "[[release notes|news/version_2.2.1]]"
-msgstr "[[یادداشت‌های انتشار|news/version_2.2.1]]"
+#| msgid "[[release notes|news/version_2.3]]"
+msgid "[[release notes|news/version_2.3]]"
+msgstr "[[یادداشت‌های انتشار|news/version_2.3]]"

wiki/src/inc/stable_i386_release_notes.fr.po

@@ -20,5 +20,5 @@ msgstr ""
 #.  Note for translators: make sure that the translation of this link
 #. integrates well with /doc/first_steps/upgrade. 
 #. type: Content of: outside any tag (error?)
-msgid "[[release notes|news/version_2.2.1]]"
-msgstr "[[Notes de version|news/version_2.2.1]]"
+msgid "[[release notes|news/version_2.3]]"
+msgstr "[[Notes de version|news/version_2.3]]"

wiki/src/inc/stable_i386_release_notes.html

 <!-- Note for translators: make sure that the translation of this link
 integrates well with /doc/first_steps/upgrade. -->
 
-[[release notes|news/version_2.2.1]]
+[[release notes|news/version_2.3]]

wiki/src/inc/stable_i386_release_notes.pt.po

@@ -18,5 +18,5 @@ msgstr ""
 #.  Note for translators: make sure that the translation of this link
 #. integrates well with /doc/first_steps/upgrade. 
 #. type: Content of: outside any tag (error?)
-msgid "[[release notes|news/version_2.2.1]]"
-msgstr "[[notas de lançamento|news/version_2.2.1]]"
+msgid "[[release notes|news/version_2.3]]"
+msgstr "[[notas de lançamento|news/version_2.3]]"

wiki/src/inc/stable_i386_torrent_sig_url.html

-https://tails.boum.org/torrents/files/tails-i386-2.2.1.torrent.sig
+https://tails.boum.org/torrents/files/tails-i386-2.3.torrent.sig

wiki/src/inc/stable_i386_torrent_url.html

-https://tails.boum.org/torrents/files/tails-i386-2.2.1.torrent
+https://tails.boum.org/torrents/files/tails-i386-2.3.torrent

wiki/src/inc/stable_i386_version.html

-2.2.1
+2.3