Tidy up "services_dhcp_relay.php" XHTML

Add "closehead" variable and close HEAD manually
Add CDATA sections to scripts
Add summary to TABLES
Add missing closing FORM if DHCP is enabled
Update HTML Boolean operators
Close INPUT
Tidy up "services_dhcp" XHTML

Update alert message
Add "closehead" variable and manually close HEAD
Add CDATA sections to scripts
Add summart to tables
Update HTML Boolean operators
Close INPUT
Add missing closing P tag
Remove empty TFOOT
Add missing opening TR tag, closing TD tag and closing P tag
Remove duplicate closing TR
Tidy up "services_dhcpv6_realy.php" XHTML

Add "closehead" variable and manually close HEAD
Add CDATA sections to scripts
Add summary to tables
Add missing closing FORM if DHCPV6 is running
Update HTML Boolean operators
Close INPUT
Tidy up "services_dhcpv6" XHTML

Update alert message
Add "closehead" variable and manually close HEAD
Add CDATA sections to script
Add SUMMARY to tables
Update HTML Boolean operators
Close INPUT
Add missing closing P tag
Remove empty TFOOT tag
Deprecate ampersand
Tidy up "services_router_advertisements" XHTML

Add CDATA sections to script
Add SUMMARY to table
Update HTML Boolean operators
Add dummy table row, but don't display it
Close INPUT
Tidy up "services_dnsmasq" XHTML

Add "closehead" variable and manually close HEAD
Add CDATA sections to scripts
Add SUMMARY to tables
Update HTML Boolean operators
Close INPUT
Move TFOOT between THEAD and TBODY (quirk of HTML)
Move NOWRAP into class statement
Close IMG and add ALT
Deprecate ampersand
Add table row, but don't display it
Remove duplicate opening and closing TR tags
Add missing closing BODY tag and closing HTML tag
Tidy up "services_unbound" XHTML

Add "cloeahead" variable and manually close HEAD
Add CDATA sections to scripts
Add SUMMARY to tables
Update HTML Boolean operators
Close INPUT
Remove duplicate closing TD tag
Move TFOOT tag between THEAD and TBODY (quirk of HTML)
Add dummy table row, but don't display it
Remove duplicate opening and closing TR tags
Closing IMG and add ALT
Deprecate ampersand
Merge pull request #1062 from ExolonDX/branch_master_18
Merge pull request #1061 from ExolonDX/branch_master_17
Merge pull request #1060 from ExolonDX/branch_master_16
Merge pull request #1059 from ExolonDX/branch_master_15
Merge pull request #1058 from ExolonDX/branch_master_14
Merge pull request #1057 from ExolonDX/branch_master_13
Merge pull request #1056 from ExolonDX/branch_master_12