Rename package from 'nw' to 'novelwriter' (#868)

* Rename nw folder to novelwriter
* Rename nw to novelwriter in auxiliary files
* Rename nw to novelwriter in main app source
* Rename nw to novelwriter in tests
* Make setup script for pdf docs less spammy

tests/test_dialogs/test_dlg_wordlist.py

@@ -28,8 +28,8 @@ from PyQt5.QtWidgets import QDialog, QMessageBox, QAction
 from tools import writeFile, readFile, getGuiItem
 from mock import causeOSError
 
-from nw.dialogs import GuiWordList
-from nw.constants import nwFiles
+from novelwriter.dialogs import GuiWordList
+from novelwriter.constants import nwFiles
 
 keyDelay = 2
 typeDelay = 1