Update security polling status for Debian and derivatives

Current versions.
Replace MYSQL_inc with MYSQL_CFLAGS

Part of #1748
Replace MYSQL_lib with MYSQL_LIBS

Part of #1748
Allow overriding of LDAP_LIBS

Part of #1826
Sync schema with mydns-ng
Support mydns-ng style Y/N active field.
Restore 'aux'
Merge pull request #1886 from zeha/secpoll-debian

Update security polling status for Debian
docs: recursor/running: cleanup

Mark all config vars bold, all commands/parameters preformatted,
remove double escaping.
docs: recursor/running: add new(er) commands
make latency & qsize reporting 'live'. Plus fix that we only reported the qsize of the first distributor.
Merge branch 'master' of github.com:PowerDNS/pdns
mind04 discovered we count corrupt packets and EAGAIN situations as validly received packets, skewing the udp questions/answers graphs on auth.
remove additional layer of trailing . stripping, which broke MX records to the root in the BIND backend. Should close #1243.
root MX test
don't do time(0) under signature cache lock
Merge branch 'master' of github.com:PowerDNS/pdns
add signatures metric to auth, so we can plot signatures/second
test NS and CNAME pointing at the root
Merge pull request #1925 from cmouse/mydns-schema-fix

Add active to schema as expected by the code