add encoding support to file in/out node (#2066)

* add encoding support to file in/out node

* update package.json

* change default encoding label: 'none' -> 'utf8[default]'

* add a missing message catalogue entry

* change default encoding label

packages/node_modules/@node-red/nodes/locales/en-US/messages.json

@@ -860,6 +860,7 @@
             "filelabel": "file",
             "sendError": "Send message on error (legacy mode)",
             "deletelabel": "delete __file__",
+            "encoding": "Encoding"
             "utf8String": "UTF8 string",
             "binaryBuffer": "binary buffer"
         },
@@ -879,6 +880,21 @@
             "deletedfile": "deleted file: __file__",
             "appendedfile": "appended to file: __file__"
         },
+        "encoding": {
+            "none": "default",
+            "native": "Native",
+            "unicode": "Unicode",
+            "japanese": "Japanese",
+            "chinese": "Chinese",
+            "korean": "Korean",
+            "taiwan": "Taiwan/Hong Kong",
+            "windows": "Windows codepages",
+            "iso": "ISO codepages",
+            "ibm": "IBM codepages",
+            "mac": "Mac codepages",
+            "koi8": "KOI8 codepages",
+            "misc": "Miscellaneous"
+        },
         "errors": {
             "nofilename": "No filename specified",
             "invaliddelete": "Warning: Invalid delete. Please use specific delete option in config dialog.",

packages/node_modules/@node-red/nodes/locales/en-US/storage/50-file.html

@@ -32,6 +32,7 @@
     <p>It can be configured to overwrite the entire file rather than append. For example,
     when writing binary data to a file, such as an image, this option should be used
     and the option to append a newline should be disabled.</p>
+    <p>Encoding of data written to a file can be specified from list of encodings.</p>
     <p>Alternatively, this node can be configured to delete the file.</p>
 </script>
 
@@ -63,6 +64,7 @@
     split into smaller buffer chunks - the chunk size being operating system dependant, but typically 64k (Linux/Mac) or 41k (Windows).</p>
     <p>When split into multiple messages, each message will have a <code>parts</code>
     property set, forming a complete message sequence.</p>
+    <p>Encoding of input data can be specified from list of encodings if output format is string.</p>
     <h4>Legacy error handling</h4>
     <p>Before Node-RED 0.17, if this node hit an error whilst reading the file, it would
     send a message with no <code>msg.payload</code> and <code>msg.error</code> set to the