Merge with GPL 376_3602 + 3561 BWDPI components (currently fails to build).  Kept old NTP code for now (new one is quirky), and our own VPN pages (new ones are a major rework)
Merged with GPL 3626 (from AC68)
Disable automatic CFE upgrade on RT-AC68U
ndisc6: Updated gitignore, removed built bins from repo
libnmp: Add prebuilt binaries (more closed-source fun...)
Bumped revision to 376.49 alpha 1
openssl: Disable deprecated/unsafe SSLv2 and v3 protocols at build time.  We already have the rest of the firmware set to use TLS 1.0.
Merge branch '3602'
webui: convert is_* functions to the new validator methods in our own pages