enc 0.1

Initial release.

• utf8 class with constructor, coercion, combination, formatting, printing, and checked updates.
• to_encoding() performs deep encoding conversion of objects, including names and other attributes. Variants: to_utf8(), to_native(), to_latin1() and to_alien().
• encoding(), returns "ASCII" for pure ASCII strings and behaves identically to base::Encoding() otherwise.
• all_utf8(), returns a logical scalar that indicates if all elements of a character vector are UTF-8 encoded; this includes pure ASCII strings.
• read_lines_enc(), try_read_lines_enc(), and write_lines_enc() for robust reading and writing of text files. Returns/accepts objects of class utf8.
• transform_lines_enc(), with robust handling if only some files could be transformed in transform_lines_enc(). Uses try_read_lines_enc(), therefore only warns if file is missing. Auto-detects and maintains EOL delimiter.