emailrelay: added configuration options

- moved from net to mail category
- removed no-ssl package and added ssl support as configuration option (default enabled)
- added configuration option to support extended logging (default disabled)
- disabled build of test tools
- added LEDE compatibility (support for openssl without SSL3)

Signed-off-by: Federico Di Marco <fededim@gmail.com>

mail/emailrelay/patches/010-ssl3-fix.patch

@@ -0,0 +1,13 @@
+--- a/src/gssl/gssl_openssl.cpp
++++ b/src/gssl/gssl_openssl.cpp
+@@ -292,8 +292,10 @@ GSsl::Context::Context( const std::strin
+ {
+ 	if( (flags&3U) == 2U )
+ 		m_ssl_ctx = SSL_CTX_new(SSLv23_method()) ;
++#ifdef SSL3_SUPPORT
+ 	else if( (flags&3U) == 3U )
+ 		m_ssl_ctx = SSL_CTX_new(SSLv3_method()) ;
++#endif
+ 	else
+ 		m_ssl_ctx = SSL_CTX_new(TLSv1_method()) ;
+