luasec: Add TLS 1.1 and TLS 1.2
luasec: reduse send buffer size to 4KiB
luasec: https: do not set SSL options
luasec: allow set cipher suit
xavante: https: disable SSL options
xavante: fix persistent http/1.1 connections
openssl: disable DH support
pppd: restart connection if it was idle for 6 hours