Move all the messages from i18n.php to json

This will require the import of all the translations from
the ext-universallanguageselector group
to the ext-jquery-uls group.

The messages already exists, so they are not re-imported.
In the next sync when the translatewiki config is updated,
the json message group of ULS will claim ownership of these messages.

Full export is needed to populate the messages in the existing json
files.

Change-Id: I6c5de42784971f59d1ca6b975095137a64c87363

i18n/en.json

@@ -1,11 +1,22 @@
 {
 "@metadata": {
 	"authors": [
+		"Nike",
+		"Kunal Mehta",
+		"Niharika",
 		"Amire80",
 		"Santhosh Thottingal"
 	],
 	"message-documentation": "qqq"
 },
+"uls-desc": "Gives the user several ways to select a language and to adjust language settings",
+"uls-plang-title-languages": "Languages",
+"uls-ime-helppage": "https://www.mediawiki.org/wiki/Special:MyLanguage/Help:Extension:UniversalLanguageSelector/Input_methods/$1",
+"ext-uls-select-language-settings-icon-tooltip": "Language settings",
+"ext-uls-undo-language-tooltip-text": "Language changed from $1",
+"ext-uls-language-settings-preferences-link": "More language settings",
+"uls-betafeature-label": "Compact language links",
+"uls-betafeature-desc": "Show a shorter version of the language list, with just the languages that are more relevant to you.",
 "ext-uls-display-settings-title": "Display settings",
 "ext-uls-display-settings-language-tab": "Language",
 "ext-uls-display-settings-fonts-tab": "Fonts",