Update from 1.8.0 to 1.9.0.

<ChangeLog>

*) Feature: request routing by arguments, headers, and cookies.

*) Feature: route matching patterns allow a wildcard in the middle.

*) Feature: POST operation for appending elements to arrays in

configuration.

*) Feature: support for changing credentials using CAP_SETUID and

CAP_SETGID capabilities on Linux without running main process as
privileged user.

*) Bugfix: memory leak in the router process might have happened when a

client prematurely closed the connection.

*) Bugfix: applying a large configuration might have failed.

*) Bugfix: PUT and DELETE operations on array elements in configuration

did not work.

*) Bugfix: request schema in applications did not reflect TLS

connections.

*) Bugfix: restored compatibility with Node.js applications that use

ServerResponse._implicitHeader() function; the bug had appeared in
1.7.

*) Bugfix: various compatibility issues with Node.js applications.

</ChangeLog>