#19981: fix typo in email.mailbox docs.  Patch by Claudiu Popa.
#19981: merge with 3.3.
Fix C++ header usage.  This __STDC_LIMIT_MACROS scheme can still be subverted
by including stdint.h before mpdecimal.h.  In that case the only option left
is to compile with -D_STDC_LIMIT_MACROS.
Merge from 3.3.