Version 2.7.11: the Windows launcher and install-doc fixes

Ships the launcher/doc commit on top of v2.7.10 as a release:
- start.bat passes --db/DB to the server (it only stored the value before) and
  sends --gsmtap-port only for gsmtap capture, like start.sh;
- both .bat launchers quote their values and keep the quoting of pass-through
  options, so paths with spaces work (--db, --web-dir, --pcap, --output);
- the READMEs describe both install paths (release artifacts or a git clone)
  and document the launchers and the Windows python-on-PATH requirement.

Version strings in version.py, pyproject.toml, PWA_VERSION and the version
test move together; SW cache simtrace-analyser-v93.

frontend/sw.js

@@ -1,4 +1,4 @@
-const CACHE = 'simtrace-analyser-v92';
+const CACHE = 'simtrace-analyser-v93';
 
 const PRECACHE = [
     'index.html',