Fix pasteinto error when clipboard text has surrounding whitespace. (#262)

`pasteinto` is called by `surroundFunc` which a string into whitespace
delimited arguments. Surrounding whitespace in the link to be copied
thus errors due to an unhandled number of arguments.

The now fixed error can be recreated by using `yy` to yank a line and
then using <A-p> to paste the link over a word. Similarly, `yW` will
reproduce the error if the link has a trailing whitespace.

`pasteinto` will still error if the link contains internal whitespace,
but this is more reasonable behavior. Fixing this will require tweaking
the regex `surroundFunc` uses to split up arguments.

main.ts

@@ -521,7 +521,7 @@ export default class VimrcPlugin extends Plugin {
 			// Using the register for when this.yankToSystemClipboard == false
 			surroundFunc(
 				['[',
-				 '](' + vimObject.getRegisterController().getRegister('yank').keyBuffer + ")"]);
+				 '](' + vimObject.getRegisterController().getRegister('yank').keyBuffer[0].trim() + ")"]);
 		})
 
 		var editor = this.getActiveView().editor;