Fix bugs related to reconnecting

Disconnect and reconnecting works:
```
:IcedConnect | IcedDisconnect | IcedConnect
```

Makes `:IcedReconnect` work if a connection is not already established.

autoload/iced/di/channel/neovim.vim

@@ -36,6 +36,7 @@ function! s:ch.open(address, options) abort
 endfunction
 
 function! s:ch.close(handler) abort
+  let self['is_connected'] = v:false
   return chanclose(s:ch_id(a:handler))
 endfunction
 

autoload/iced/nrepl.vim

@@ -88,7 +88,7 @@ endfunction
 " HANDLER {{{
 function! s:get_message_id(x) abort
   let x = a:x
-  if type(x) == type([])
+  if type(x) == type([]) && len(x) > 0
     let x = x[0]
   endif
   if type(x) == type({})
@@ -321,12 +321,15 @@ function! iced#nrepl#disconnect() abort " {{{
     call iced#nrepl#sync#close(id)
   endfor
   call iced#di#get('channel').close(s:nrepl['channel'])
-  call s:initialize_nrepl()
+  let s:nrepl = s:initialize_nrepl()
   call iced#cache#clear()
+  call iced#message#info('disconnected')
 endfunction " }}}
 
 function! iced#nrepl#reconnect() abort " {{{
-  if !iced#nrepl#is_connected() | return | endif
+  if !iced#nrepl#is_connected()
+    return iced#nrepl#connect#auto()
+  endif
 
   let port = s:nrepl['port']
   call iced#nrepl#disconnect()

message/iced/en.txt

@@ -6,6 +6,7 @@
   'not_connected':      'Not connected.',
   'try_connect':        'Not connected. Try `:IcedConnect <port>`',
   'connected':          'Connected.',
+  'disconnected':       'Disconnected.',
   'interrupted':        'Interrupted.',
   'reading':            'Still reading..',
   'not_found':          'Not found.',