ParseOptions: Add read_tags

[Serial-ATA]

Summary

Unexpectedly, many projects pull in Lofty solely for its property reading. Each time it is used for this purpose, however, all of the tags are still being parsed unnecessarily.

Just as one can skip property reading with ParseOptions::read_properties(false), it may be worth adding ParseOptions::read_tags().

API design

impl ParseOptions {
    pub fn read_tags(&mut self, read_tags: bool) -> Self;
}