README: Add instructions for Windows with screenshots

Also add a note about installation
6 jobs for <span class="ref-name">misc-fixes</span> in 17 minutes and 25 seconds (queued for 1 second)
Status Job ID Name Coverage
  Preparation
passed #243911
gst indent

00:00:16

passed #243910
manifest

00:00:19

 
  Build
passed #243912
build fedora x86_64

00:04:33

passed #243913
build nodebug fedora x86_64

00:04:53

 
  Test
passed #243914
check fedora

00:04:05

passed #243915
integration testsuites fedora

00:12:12