also includes commented-out tests for functionality that i discovered we never
provided, namely position and length information at the granularity of
HParsedTokens. at the moment, these fields always seem to be 0. we should
probably fix that or get rid of them. in the latter case it might make sense
to move this information to HParseResult, so the user can get access to it via
h_action() as needed.

Fix pointer signedness warning in h_literal()

See merge request hammer/hammer!26

Unroll djbhash for ~25% speedup

See merge request hammer/hammer!24

Hammer arena malloc speedup

See merge request hammer/hammer!23

Hammer speedup

See merge request hammer/hammer!22

Provide an alternate interface to the arena allocator to avoid wasting time on unnecessary calls to memset()

Eliminate unnecessary hash computations in the packrat backend (roughly 2.5x speed in one benchmark)

Hammer gprof

See merge request hammer/hammer!21

Support --gprof build flag

See merge request hammer/hammer!20

h_drop_from

See merge request hammer/hammer!19

A working h_drop_from which rewrites its underlying sequence as a sequence containing some ignored parsers.

enable h_repeat_n() for CF backends

See merge request hammer/hammer!18

Test/fix h_bits(0, ...)

See merge request hammer/hammer!17

fix string escaping in json output

See merge request hammer/hammer!15

Support custom pretty-printers with USER token types

See merge request hammer/hammer!14

add combinators h_skip, h_seek, h_tell

See merge request hammer/hammer!13

revert changes to examples/base64 - bad merge

See merge request hammer/hammer!12

add const to the pointer arg to h_make_bytes

See merge request hammer/hammer!11

Compiler fixes

See merge request hammer/hammer!10