Improve server constructor argument validation error reporting.
Merge pull request #1005 from philbooth/master

Improve server constructor argument validation error reporting
fixed some typos

server.ext -> options -> *after* looks like it had its description copy/pasted from *before*. Adjusted the description to be logical, but this should be checked by someone more familiar with its implementation.
fix bad fragment identifier link

and a minor typo.
Merge pull request #1006 from dguzzo/patch-1

fixed some typos
Merge pull request #1007 from dguzzo/master

fix bad fragment-identifier markdown link