Version 0.9.15
- Delete options R_ls_env_tol, R_objbr_labelerr, R_show_arg_help.
- New options: R_clear_console, R_debug, R_auto_start, R_dbg_jump.
- Replace options R_in_buffer, R_term and R_term_cmd with a single option: R_external_term.
- Make R_rmdchunk more flexible.
- Change default key binding for calling debug() from \db to \bg to avoid conflict with \d (send line).
- Require either Neovim >= 0.4.3 or Vim >= 8.1.1705.