fix automake errors

src/plugins/fetchinfo/Makefile.am:83: warning: EXTRA_DIST multiply defined in condition TRUE ...
src/plugins/fetchinfo/Makefile.am:8: ... 'EXTRA_DIST' previously defined here
src/plugins/perl/Makefile.am:38: warning: EXTRA_DIST multiply defined in condition TRUE ...
src/plugins/perl/Makefile.am:8: ... 'EXTRA_DIST' previously defined here
src/plugins/pgpinline/Makefile.am:7: warning: appdata_DATA multiply defined in condition TRUE ...
src/plugins/pgpinline/Makefile.am:5: ... 'appdata_DATA' previously defined here
src/plugins/spamassassin/Makefile.am:42: warning: EXTRA_DIST multiply defined in condition TRUE ...
src/plugins/spamassassin/Makefile.am:8: ... 'EXTRA_DIST' previously defined here

Signed-off-by: Igor Gnatenko <i.gnatenko.brain@gmail.com>
i18n: improve translations

Signed-off-by: Igor Gnatenko <i.gnatenko.brain@gmail.com>