Copy `LAST_JEDI_COMPLETIONS` to cell document so that `completionItem/resolve` will work#663

hjr265 wants to merge 3 commits intopython-lsp:developpython-lsp/python-lsp-server:developfrom

hjr265:copy-last-jedi-completionshjr265/python-lsp-server:copy-last-jedi-completionsCopy head branch name to clipboard