Descriptive name error for uniE4D1.salt01 and inconsistencies with related glyphs

[knutnergaard]

The stylistic alternate for uniE4D1.salt01, angled (regular) single-stroke caesura, has the same descriptive name as it's base glyph uniE4D1 (caesuraSingleStroke), and should be renamed to caesuraSingleStrokeAlt

Also, there is inconsistency with the naming/appearance/encoding of the different caesura glyphs. uniE4D1.salt01, caesuraSingleStroke, which rather should be named caesuraSingleStrokeAlt, is linked to the regular double-stroke caesura rather than the single stroke caesura (U+E4D7), which would be more logical. On the other hand U+E4D7, caesuraSingleStroke, is visually equivalent to U+E4D3, caesuraShort, rather than the regular caesura, in that its stroke is vertical, not diagonal.

[dspreadbury]

We don't have quite the same hard and fast rules about changing the names of optional glyphs as we do for recommended glyphs, so provided there are no howls of objection from the community, I think it's OK for us to review these glyphs as suggested.