Switched the default library behavior to IDNA2008 as amended by TR#46 (non-transitional). That default behavior is enabled when no flags are specified to function calls. Applications can utilize the %IDN2_NO_TR46 flag to switch to the unamended IDNA2008. This is done in the interest of interoperability based on the fact that this is what application writers care about rather than strict compliance with a particular protocol.
Fixed memleak in idn2_to_unicode_8zlz().
Return error (IDN2_ICONV_FAIL) on charset conversion errors.
Fixed issue with STD3 rules applying in non-transitional TR46 mode.