mutation testing
temp rspec changes (to include profile)
mutant tweaks (cli)

- don’t pass environment. it is not used
- don’t dynamically determine program name
- use relative VERSION reference
- fix base_dir override and tests
- better tests that leverage exit
- less filename manipulation
- binder#book_title used for filename too
- make spider#multi_site a first class variable
- no need to set OptionParser#program_name and banner
fix mutants (chapter, editor)

- test editor#title_path and multiple chapters
- fix editor#title with no title
- test basic case of chapter#body being an array
- transition spider#multi_site? to plain multi_site
mutant fixes (page_db)

Use an actual file to test truncation.
mutant tests speaker
test/trim runner