Upgraded opcode extension support to handle more than one opcode per extension.

src/lib-sieve/cmd-redirect.c

src/lib-sieve/ext-envelope.c

src/lib-sieve/ext-fileinto.c

src/lib-sieve/ext-reject.c

...gins/comparator-i-ascii-numeric/ext-cmp-i-ascii-numeric.c

src/lib-sieve/plugins/imapflags/cmd-addflag.c

src/lib-sieve/plugins/imapflags/cmd-removeflag.c

src/lib-sieve/plugins/imapflags/cmd-setflag.c

src/lib-sieve/plugins/imapflags/ext-imapflags-common.c

src/lib-sieve/plugins/imapflags/ext-imapflags-common.h

src/lib-sieve/plugins/imapflags/ext-imapflags.c

src/lib-sieve/plugins/regex/ext-regex.c

src/lib-sieve/plugins/relational/ext-relational.c

src/lib-sieve/plugins/subaddress/ext-subaddress.c

src/lib-sieve/plugins/vacation/ext-vacation.c

src/lib-sieve/sieve-address-parts.c

src/lib-sieve/sieve-code.c

src/lib-sieve/sieve-code.h

src/lib-sieve/sieve-commands.c

src/lib-sieve/sieve-comparators.c