Minor copy edits to dead code workshop - #1679

Changed pages include:

• index.html - view
• 404.html - view
• complexity/index.html - view
• decomposition/index.html - view
• guides/index.html - view
• how-this-works/index.html - view
• launch/index.html - view
• legacy/index.html - view
• logic/index.html - view
• overview/index.html - view

There are more changes not included in the list