Add toggles to control the search flags (no RegEx, case-sensitive, etc.)

[MasterInQuestion]

    Several toggles should be added to the interface, when accessing the "Search Text" function in "Snippets":     To better control the search behaviors.

    Namely:     |1| Word-Only [ Default: false. Equivalently wrap the pattern in /(?<![^\W_])...(?![^\W_])/. ]     |2| Case-Sensitive [ Default: false. ]     |3| RegEx [ Default: true. Treat the pattern as RegEx or literal. ]     |4| Multi-line [ Default: true. Use "m" flag for RegEx. ]

    The search settings should persist, between different invocations of "Search Text" on the same page (and not across pages / browser tabs).     A button to quickly cancel previous highlighting would also help.