Fingerprint: Add Show instance for easier debugging

Signed-off-by: Austin Seipp <aseipp@pobox.com>
Fingerprint: Add getFileHash

Signed-off-by: Austin Seipp <aseipp@pobox.com>
Fix -Werror failure in GHC.Fingerprint

Signed-off-by: Austin Seipp <aseipp@pobox.com>
Remove trailing whitespace from GHC.Fingerprint.*

Signed-off-by: Austin Seipp <aseipp@pobox.com>
Comments only

Add note for Integre constant folding
Fix off-by-one error in the IO manager

The last enabled event manager was being needlessly restarted after
increasing the number of capabilities at runtime.
Switch IO manager to a mutable hashtable

This data structure (IntTable) provides a similar API to its predecessor
(IntMap), at half the number of lines in size.

When tested in isolation using criterion, IntTable is much faster than
IntMap: over 15x, according to my criterion benchmarks.

This translates into a measurable improvement when used in the IO manager:
using weighttp to benchmark acme-http under various configurations on two
32-core Linux servers connected by a 10gbE network, I see between a 3%
and 10% increase in requests served per second compared to IntMap.

Signed-off-by: Andreas Voellmy <andreas.voellmy@gmail.com>