document some odds and ends

add some benchmarks

add first context support, design-issues.md

fix package auto-calc for With and methods.

table buffer bugfix, README cleanup middleware docs

some fixes and Errf

fix Fmt typo, add time middleware

prettier tables, .Fatal

rudimentary Lctl command

documentation improvements

- changed behavior of ApplyOpts.PreservedLabels to better fit the name
and be more orthogonal.