std.uni: optimize simpleCaseTable

[dkorpel]

Cuts size of simpleCaseTable entries in half (8 -> 4 bytes), reducing table size from 24 Kb to 12 Kb. Still only 22 out of 32 bits per entry are actually used, so could be optimized further. Using plain integers saves 10 ms semantic2 compile time.

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[rikkimax]

Certainly better, but I am surprised it has only got 10ms off.

[dkorpel]

The FullCaseEntry table is 50 kb currently, I expect optimizing that to shave off another 20 ms.

[dkorpel]

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