proposal: a fragility-based Ashenzari + a Curses reform

[Pollen_Golem]

Basic idea can be laid out like this:

• non-book artefacts and blue items can have up to 1 quality (*drain,*contam,*fragile...) that produces a nasty effect on unequip
• remove curses and the Scroll of Remove Curse; introduce the Scroll of Impart Fragility
• Scroll of Impart Fragility gives a chosen item the Fragile property (item destroys on unequip)
• if the chosen item already has a take-off negative property, Scroll of Impart Fragility overwrites it without incurring the take-off effect
• you can press escape to cancel the scroll, so read-identifying it does not force you to make anything Fragile
• Scroll of Impart Fragility should be relatively common
• proposed Ash is to Fragile items what current Ash is to Cursed items
• proposed Ash does not corrupt scrolls
• proposed Ash does not "enhance" the use of any scroll
• if fragility usually expires after the item is used for a while, proposed Ash prevents this from happening
• buff Ash

Before digging into the deeper implications of this proposal, note that this solves the frustration of not getting the desired kind of "Curse X" scroll with an Ash character, without making it trivial to fully bind yourself at a meaningless cost, which is what opponents to curse-streamlining worry about.