[Libguestfs] [PATCH libnbd 0/9] Add Enum and Flags types.

This largish series adds several new features to the generator. Enum maps to enumerated types (like enum in C). The only current use for this is replacing the nbd_set_tls (nbd, 0/1/2) parameter with LIBNBD_TLS_DISABLE, LIBNBD_TLS_ALLOW, LIBNBD_TLS_REQUIRE (and natural equivalents in other programming languages). Flags maps to any uint32_t bitmask. It is basically a non-optional, generalized variation on OFlags with some nice features. Two commits also add checking so that we check that the Enum, Flags or OFlags parameters don't contain values which are invalid at the time of compilation. This breaks new caller / old DLL at runtime (which may not be a bad thing). Note that at least patch #9 and maybe even #7 and #8 are mainly being posted for discussion. Rich.