Full support fo LSP

• Add multiply provider support for all features.
• Add documentLink support
• Add documentHighlight support
• Add foldingRange support
• Add support of documentSelector same as VSCode
• Add keepfocus option for open_terminal.
• Add onTypeFormat feature for language server
• Add onTypeFormat support for tsserver.
• Add callAsync for async request to vim.
• Add CocActionAsync function send async request to server.
• Fix diagnostic and arguments of tsserver.
• Fix sometimes client status invalid.
• Fix window/showMessageRequest request.