Fix typos and inconsistencies for HEAD (take 7)

Hello hackers,

Please consider fixing the next pack of typos and inconsistencies in the
tree:
7.1. h04m05s06 -> h04mm05s06 (in fact it's broken since 6af04882, but
h04mm05s06.789 still accepted)
7.2. hasbucketcleanup -> hashbucketcleanup
7.3. _hashm_spare -> hashm_spares
7.4. hashtbl -> hash table
7.5. HAS_RELFILENODES -> XINFO_HAS_RELFILENODES
7.6. HAS_SUBXACT -> XINFO_HAS_SUBXACT
7.7. HAVE_FCVT -> remove (survived after ff4628f3)
7.8. HAVE_FINITE -> remove (orphaned after cac2d912)
7.9. HAVE_STRUCT_SOCKADDR_UN -> remove (not used since introduction in
399a36a7)
7.10. HAVE_SYSCONF -> remove (survived after ff4628f3)
7.11. HAVE_ZLIB -> HAVE_LIBZ
7.12. HEAP_CLEAN -> XLOG_HEAP2_CLEAN
7.13. HEAP_CONTAINS_NEW_TUPLE_DATA -> XLH_UPDATE_CONTAINS_NEW_TUPLE,
XLOG_HEAP_CONTAINS_OLD_TUPLE -> XLH_UPDATE_CONTAINS_OLD_TUPLE,
XLOG_HEAP_CONTAINS_OLD_KEY -> XLH_UPDATE_CONTAINS_OLD_KEY,
XLOG_HEAP_PREFIX_FROM_OLD -> XLH_UPDATE_PREFIX_FROM_OLD,
XLOG_HEAP_SUFFIX_FROM_OLD -> XLH_UPDATE_SUFFIX_FROM_OLD (renamed in
168d5805)
7.14. HEAP_FREEZE -> FREEZE_PAGE (an inconsistency since introduction in
48188e16)
7.15. heapio.c -> hio.c
7.16. heap_newpage -> XLOG_FPI (orphaned since 54685338)
7.17. heaxadecimal -> hexadecimal
7.18. hostlen -> nodelen, host -> node, serv -> service, servlen ->
servicelen
7.19. i386s -> x86_64
7.20. IConst/FConst  -> ICONST/FCONST
7.21. imit -> limit
7.22. IN_ARCHIVE_RECOVERY -> DB_IN_ARCHIVE_RECOVERY
7.23. ind_arraysize, ind_value -> ind_arrsize, ind_pointer
7.24. index_getnext -> index_getnext_slot
7.25. IndexTupleVector -> IndexTuple vector
7.26. innerConsistent -> innerConsistentFn
7.27. in-progres -> in-progress
7.28. inspire with -> inspired by the (sync with 192b0c94)
7.29. internalerrpos -> internalerrposition
7.30. internal_procname -> internal_proname
7.31. interruptOK -> remove (orphaned after d0699571)
7.32. intratransaction -> intra-transaction
7.33. InvalidOffset -> InvalidOffsetNumber
7.34. invtrans -> invtransfn
7.35. isbuiltin -> fmgr_isbuiltin
7.36. iself -> itself
7.37. isnoinherit -> noinherit
7.38. ISO_DATES -> USE_ISO_DATES
7.39. isParentRoot -> remove (orphaned after 218f5158)
7.40. isPrefix -> prefix
7.41. ItemPointerIsMax -> remove (orphaned after e20c70cb)
7.42. itemsin -> items in
7.43. jbVal -> jbval
7.44. json_plperl -> jsonb_plperlu
7.45. jvbBinary -> jbvBinary
7.46. keyAttrs -> attrKind
7.47. keyinfo -> key info
7.48. key_modified -> key_changed
7.49. killitems -> killedItems
7.50. KnownAssignedTransactions -> KnownAssignedTransactionIds

Also, I found e-mail headers in optimizer/plan/README not relevant, so I
propose to remove them.
And another finding is related to the sleep effective resolution. `man 7
time` says "Since kernel 2.6.13, the HZ value is a kernel configuration 
parameter  and  can  be 100, 250 (the default) ...", so the 10
milliseconds is not the most common effective resolution nowadays.
I propose the corresponding patch for pgsleep.c, but we have a similar
statement in doc/.../config.sgml. I think It should be fixed too.

Best regards,
Alexander