Let's keep the main launcher novelWriter.py and let setuptools handle the rest

novelWriter.py

@@ -0,0 +1,49 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+import sys
+
+if sys.hexversion < 0x030500F0:
+    print("ERROR: At least Python 3.5 is required")
+    exit(1)
+
+try:
+    import PyQt5.QtWidgets
+    import PyQt5.QtGui
+    import PyQt5.QtCore
+except:
+    print("ERROR: Failed to load dependency python3-pyqt5")
+    exit(1)
+
+try:
+    import PyQt5.QtSvg
+except:
+    print("ERROR: Failed to load dependency python3-pyqt5.qtsvg")
+    exit(1)
+
+try:
+    import lxml
+except:
+    print("ERROR: Failed to load dependency python3-lxml")
+    exit(1)
+
+try:
+    import appdirs
+except:
+    print("ERROR: Failed to load dependency python3-appdirs")
+    exit(1)
+
+spellPack = None
+try:
+    import enchant
+    spellPack = "enchant"
+except:
+    print("WARNING: No spell check library found.")
+    print("Please install python3-enchant if you want to use spell checking")
+
+if __name__ == "__main__":
+    import nw
+    inArgs = sys.argv[1:]
+    if spellPack is not None:
+        inArgs.append("--spell=%s" % spellPack)
+    nw.main(inArgs)