[libcxx][docs] updates the ranges status paper

* indicates whether work has been started or completed
* consolidates content that was split for dependency reasons (iff
  everything has been merged)
* makes things a lot more fine-grained
* turns sub-CSVs into lists
* puts links into description section and removes patch column
* adds links to c++draft on occasion

These changes heavily prioritise the the reader of the generated HTML
file, not the source.

Differential Revision: https://reviews.llvm.org/D103295