Rewrite of Phobos index page.

Make it more useful than the current outdated and irrelevant philosophy
page.
Remove useless link to obsolete wiki.
code formatting, use sink

update docs, style, use thread:id scheme

use MessageBox hash, remove running thread

use mbox address

moved import
Supplemental fix for issue 13783 in std.parallelism

`auto f(ref ubyte);` should not take an lvalue of `enum E : ubyte`.
Fixing 13783 will disallow the accepts-invalid bug.
Move last paragraph to top for easier reading.
Make std.range.recurrence safe if possible
Fix broken ddoc build for std/regex/package.d.
Update std.range.* docs.

The previous docs were simply dissected from the original std.range docs, and
the text in each module is truncated and awkward to read. The main package.d
docs were also missing links to the submodules. So, update the docs to reflect
the current state of things.
Fix broken PHOBOSSRC link.

This is caused by Ddoc's "helpful" auto-highlighting of every occurrence of the
name of the module, including places where it's not very helpful.
Merge pull request #2778 from tom-tan/safe-range-recurrence

Make std.range.Recurrence safe
Merge pull request #2773 from 9rnsr/fix13783

Supplemental fix for issue 13783 in std.parallelism
Merge pull request #2772 from quickfur/pr6989_rebase

Rebase of PR 2482: Issue 6989 - create a better string representation of Tid
Move single-element predicate-only find above subrange find
Properly document BoyerMooreFinder

Before it was ditto-ing the find(haystack, needles) docs which return a
tuple instead.
Move boyerMooreFinder above the struct so ddoc finds a parameter name.
Remove note about bug 4759, which is now resolved.
Remove broken glossary links
Don't import std.format in any public scope.

Workaround for: https://issues.dlang.org/show_bug.cgi?id=13808
allow casting Typedef to another Typedef
Merge pull request #2779 from ntrel/find-docs

Improve std.algorithm.find overload docs
List walkLength under convenience functions rather than capabilities
Merge pull request #2781 from ntrel/range-walklength-ref

std.range.primitives: List walkLength under convenience functions rather than capabilities