Add recipe for NSIS installer with pynsis

installer.cfg

@@ -0,0 +1,26 @@
+[Application]
+name=PlChat
+version=1.0
+entry_point=plchat:main
+icon = fedi.ico
+
+[Python]
+version=3.8.8
+bitness=64
+format=bundled
+
+[Include]
+pypi_wheels = python-dateutil==2.8.1
+	QtPy==1.9.0
+	keyring==22.0.1
+	PySide2==5.15.2
+	appdirs==1.4.4
+	python-magic==0.4.22
+	python-magic-bin==0.4.14
+	websockets==8.1
+
+files = LICENSE
+	fedi.svg
+	send.svg
+	unread.svg
+	COPYING