Prepare for icu66

Build fix needed for icu66 plus some other fixes:

• Fix drawing of popup menus,
• Fix generation of accept-language header which broke some websites.

Ready for beta2!

Lots of merges from upstream
Websocket fixes
Replaced the memory allocator to fix crashes and use less memory

Routine update and stability issues

Fix various oversights in the previous releases. Hopefully does not introduce too many regressions.

Last minute bugfixes

Fix problems with reference counting bitmaps, which was leading to a leak of memory and ports, and eventually would crash either the browser or the whole OS.

Ready for beta1

• Merge more changes from upstream webkit (we're now using early 2018 code)
• Formatted localized strings (no more "%d x %d pixels")
• Avoid crash in out of memory situations
• Fix missing text when complex text layout was meant to be used (fallback to simple layout until we get an acutal complex layout engine)

Stability fixes

Fix the most visible bugs from the 1.6.4 release and its huge merge campaign.
Should be a lot less crashes and youtube working again.

Bringing things up to date.

Merge a lot of changes from upstream (most of 2016 and 2017). Going further requires a newer gcc.
Probably some regressions, little testing was done so far. But also quite a lot of problems fixed.

More fixes and unoriginal description

• Fix drawing glitch due to broken clipping
• Some Fetch support so you can load logs from buildmaster web interface
• Some use-after-free and other invalid things in the network code

Stabilizing...

• Fix handling of non-HTTP errors (allow to use /etc/hosts to block ad servers without a local http server)
• Allow to disable javascript
• Change user agent so github stops complaining about deprecated safari version
• Enable Web Crypto

Bugfixes

Some important bugfixes for remaining bugs in 1.6.0.