feat(audio_prompts): add default audio prompts for narrator

feat(audio_prompts): add en_narrator_deep audio prompt for narrator
feat(audio_prompts): add en_narrator_light_bg audio prompt for narrator
fix(video.py): fix indentation and add prompt for generating thumbnail
fix(montage.py): fix indentation and add prompt for generating thumbnail
fix(montage.py): fix image download for wikimage slides

fix(speak.py): remove unused import statement
fix(speak.py): remove unused variable 'fakenames'
feat(speak.py): add function 'remove_blank_moments' to remove silent parts from audio file
feat(speak.py): add function 'optimize_string_groups' to optimize string groups for audio generation
fix(speak.py): fix comment indentation in 'generate_voice' function
fix(speak.py): remove unused imports in 'generate_voice' function
fix(speak.py): remove unused variable 'reduced_noise' in 'generate_voice' function
fix(speak.py): remove unused import statements in 'generate_voice' function
fix(speak.py): remove unused import statement for 'logging' module
fix(speak.py): remove unused print statements in 'main' function
fix(speak.py): remove unused import statement for 'logging' module
fix(speak.py): remove unused print statements in 'main' function
fix(speak.py):

fix(wiki_downloader.py): fix Google search URL to include correct query parameter
fix(wiki_downloader.py): reduce sleep time after page load to 1 second
fix(wiki_downloader.py): increase sleep time after image click to 5 seconds

musics/Ghostrifter-Official-Lost-In-Thought.txt

@@ -1,3 +1,3 @@
-Lost In Thought by Ghostrifter bit.ly/ghostrifter-yt
+Lost In Thought by Ghostrifter 
 Creative Commons — Attribution-NoDerivs 3.0 Unported — CC BY-ND 3.0
-Music promoted by https://www.chosic.com/free-music/all/
+Music promoted by chosic