[any.synop] Rename parameter of move constructor

All constructors taking an `any` name that argument `other`, except the move constructor in the synopsis (the move constructor definition says `other` too).
Apply LWG2371 from N4079.
Apply LWG2374 from N4079.
Apply LWG2390 from N4079.
Apply LWG2395 from N4079: "Preconditions: is defined nowhere"
Apply LWG2409 from N4079: "SFINAE-friendly common_type/iterator_traits should be removed from the fundamental-ts"
Apply N4078: "Fixes for optional objects"
Merge pull request #39 from jwakely/patch-4

[any.synop] Rename parameter of move constructor
Fix some broken markup in optional.html.
Apply N4067: "Experimental std::function etc."
Apply LWG2389 from N4079: "function::operator= is over-specified and handles allocators incorrectly"

This applied cleanly to the new section created by N4067.
Update the list of headers to match the latest html-doc-framework list-table design.
Update to html-doc-framework#master, and fix up a few over-long inline code blocks.