Improve NeoVimConnector::handleMetadata
Improve NeoVimConnector::handleMetadata

- Renamed parameter **error** it shadowed the
  error() method
- Moved ready() signal emit into handleMetadata
- Add comment

ngkaho1234/neovim-qt,0x90sled/neovim-qt,equalsraf/neovim-qt,ravloony/neovim-qt,equalsraf/neovim-qt,0x90sled/neovim-qt,0x90sled/neovim-qt,ravloony/neovim-qt,Pireax/neovim-qt,Pireax/neovim-qt,ngkaho1234/neovim-qt,Pireax/neovim-qt,ravloony/neovim-qt,ngkaho1234/neovim-qt,equalsraf/neovim-qt,equalsraf/neovim-qt