Added emacs server mode. Random fixes.

Replaced flyspell mode with jinx. Changes: - Added jinx package - Replaced flyspell-mode with jinx-mode in text-mode and markdown-mode - Added enchant detection that shows a helpful warning in Warnings buffer if enchant is not installed, with OS-specific install instructions If enchant isn't installed when you start Emacs, you'll see a warning popup with instructions for your OS (brew for macOS, apt for Ubuntu).