Fix manifest some uneeded files were getting in source tarball.

Also security.txt was being excluded add .flake8 to global exclude.

Author: rouilj

MANIFEST.in

@@ -1,14 +1,13 @@
 recursive-include share *
-recursive-include roundup *.*
+recursive-include roundup *.py *.txt
 recursive-include frontends *.*
 recursive-include scripts *.* *-*
 recursive-include scripts/Docker Dockerfile *.* *_*
 recursive-include tools *.* base64
 recursive-include test *.py *.txt
 recursive-include doc *.html *.png *.txt *.css *.example
 recursive-include detectors *.py README.txt
-global-exclude *.pyc *.pyo .DS_Store *.orig *.rej *~ \#*
 include demo.py *.txt
+global-exclude *.pyc *.pyo .DS_Store *.orig *.rej *~ \#* .flake8
 include doc/conf.py doc/roundup-favicon.ico
-exclude doc/security.txt
 include locale/*.po locale/*.mo locale/roundup.pot