Blender Git Loki

RNA: minor optimize for token extraction of RNA paths

- Split rna_path_token in two,
extracting bracket handling into it's own function.

- Only handle escape characters for quoted tokens.
Numbers were copied using BLI_str_unescape which is unnecessary.

- Extract text without without quotes,
use a return argument so the caller can tell if the token was quoted.
This avoids having to strip the tokens quotes afterwards.