Added TLSA Record Type for DNS

sorry, i dont know the procedure for the Ideas but i created an Idea in Vesta Bug Tracker: https://bugs.vestacp.com/issues/306 

This add one more option on the Type record in DNS Manager, no need extra validation, also the file: admin/add_dns_rec.html needs to be modified to add the new option tag.

func/main.sh

@@ -589,7 +589,7 @@ is_dbuser_format_valid() {
 
 # DNS record type validator
 is_dns_type_format_valid() {
-    known_dnstype='A,AAAA,NS,CNAME,MX,TXT,SRV,DNSKEY,KEY,IPSECKEY,PTR,SPF'
+    known_dnstype='A,AAAA,NS,CNAME,MX,TXT,SRV,DNSKEY,KEY,IPSECKEY,PTR,SPF,TLSA'
     if [ -z "$(echo $known_dnstype |grep -w $1)" ]; then
         check_result $E_INVALID "invalid dns record type format :: $1"
     fi