Move (r)ead checks back again

To the keypress, before slot selection.

This is more convenient for the common case (trying to read a
scroll), and less convenient for the case of 'trying to read a
spellbook while silenced' (or similar); in those cases, you're
back to having to use (i) to examine your spellbooks.
Improve curse weapon UI

Don't let players waste it when wielding a weapon of holy wrath;
and simplify.
Update blurry vision description
Gell's Gravitas.

A level 6 Hex/Translocation that pulls creatures towards a targeted
creature, potentially causing lots of collision damage - it's basically
a one-turn Singularity effect centered around a creature and without the
direct gravitational damage.

Appears in the book of the Warp and the book of Hinderance.

"Gell" is intended to be pronounced with a hard G.
Fix death message for collisions caused by the player character.

Was "caused by ", now is "caused by you".
Buff Singularity pull damage further.

My old testing of this was based on buggy mechanics; with the mechanics
fixed the spell proved to be underpowered.

This puts the damage slightly higher than it was in the original
implementation (d12 instead of d10 - a doubling over trunk as of the
previous commit), which puts it back at the previously established point
where it should be roughly as lethal as other level 9 spells.
Refactor away the trits array.

Also make chapter and verse 0-indexed (adding one on output only).

Hopefully this version is a little clearer?  It should give exactly
the same results as before.
Merge https://github.com/crawl-ref/crawl-ref
BUild fix, etc.