intl: Use channel instead of stream

Fixes part of #630

Author: Khader-1

assets/l10n/app_en.arb

@@ -192,7 +192,7 @@
   "@composeBoxDmContentHint": {
     "description": "Hint text for content input when sending a message to one other person.",
     "placeholders": {
-      "user": {"type": "String", "example": "stream name"}
+      "user": {"type": "String", "example": "channel name"}
     }
   },
   "composeBoxGroupDmContentHint": "Message group",
@@ -205,19 +205,19 @@
   },
   "composeBoxStreamContentHint": "Message #{stream} > {topic}",
   "@composeBoxStreamContentHint": {
-    "description": "Hint text for content input when sending a message to a stream",
+    "description": "Hint text for content input when sending a message to a channel",
     "placeholders": {
-      "stream": {"type": "String", "example": "stream name"},
+      "stream": {"type": "String", "example": "channel name"},
       "topic": {"type": "String", "example": "topic name"}
     }
   },
   "composeBoxSendTooltip": "Send",
   "@composeBoxSendTooltip":  {
     "description": "Tooltip for send button in compose box."
   },
-  "composeBoxUnknownStreamName": "(unknown stream)",
+  "composeBoxUnknownStreamName": "(unknown channel)",
   "@composeBoxUnknownStreamName": {
-    "description": "Replacement name for stream when it cannot be found in the store."
+    "description": "Replacement name for channel when it cannot be found in the store."
   },
   "composeBoxTopicHintText": "Topic",
   "@composeBoxTopicHintText":  {
@@ -344,9 +344,9 @@
   "@topicValidationErrorMandatoryButEmpty": {
     "description": "Topic validation error when topic is required but was empty."
   },
-  "subscribedToNStreams": "Subscribed to {num, plural, =0{no streams} =1{1 stream} other{{num} streams}}",
+  "subscribedToNStreams": "Subscribed to {num, plural, =0{no channels} =1{1 channel} other{{num} channels}}",
   "@subscribedToNStreams": {
-    "description": "Test page label showing number of streams user is subscribed to.",
+    "description": "Test page label showing number of channels user is subscribed to.",
     "placeholders": {
       "num": {"type": "int", "example": "4"}
     }