Respect network option with all option

[pcfreak30]

It appears that if you want to delete all transients, it assumes wp_options ($wpdb->options) and not wp_sitemeta (Due to a early return). This needs refactoring.

Thanks.

[schlessera]

Yes, the command does not seem to be multisite-aware yet.

[ocean90]

Looks like I reported the same in #41 / #42.

[schlessera]

Yes, indeed. Can you add a corresponding "Fixes #30" to your PR description, @ocean90 ?