trurl 0.4

Changes since previous release

 * --get supports showing {query:key}
 * --json outputs query pairs under "params"
 * -a is an --append shortcut
 * add --query-separator
 * add --sort-query
 * install instructions for cygwin

Bugfixes since previous release

 * build: compile with msvc again
 * components names are lower case and case sensitive
 * fixed the json output of UTF-8 sequences
 * flush stdout after handling every URL
 * mixing --json with --get is an error
 * more test cases
 * show error messsage when component setting fails
 * support "--" end-of-options argument
 * support for building with older libcurl versions
 * checksrc: check code style in CI job and with 'make checksrc'

Contributors to this release:

  Dan Fandrich, Daniel Stenberg, Emanuele Torre, Håvard Bønes,
  Krishean Draconis Sajad F. Maghrebi
