Use "atom-text-editor" tag instead of "editor[-colors]" classes This fixes the following deprecation warnings: - "Use the atom-text-editor tag instead of the editor-colors class." - "Target the selector :host, atom-text-editor instead of .editor-colors for shadow DOM support." - "Use the atom-text-editor tag instead of the editor class." - "Target the selector :host, atom-text-editor instead of .editor for shadow DOM support." Closes joaoafrmartins/seti-monokai#7, Closes joaoafrmartins/seti-monokai#8, Closes joaoafrmartins/seti-monokai#9, Closes joaoafrmartins/seti-monokai#10.