refactor: move stickers to own model

Remove from ChatModel and add StickerModel

# Conflicts:
#	src/app/chat/view.nim
#	src/status/chat.nim
#	src/status/libstatus/contracts.nim

src/status/chat.nim

@@ -5,6 +5,8 @@ import libstatus/chatCommands as status_chat_commands
 import libstatus/accounts/constants as constants
 import libstatus/types
 import stickers
+import mailservers
+
 import profile/profile
 import chat/[chat, message]
 import signals/messages

src/status/stickers.nim

@@ -8,7 +8,7 @@ from eth/common/utils import parseAddress
 import # local deps
   libstatus/types, libstatus/eth/contracts as status_contracts,
   libstatus/stickers as status_stickers, transactions
-from libstatus/utils as libstatus_utils import eth2Wei
+from libstatus/utils as libstatus_utils import eth2Wei, gwei2Wei, toUInt64
 
 logScope:
   topics = "stickers-model"