share_form
refactor into form_init
generate share link
only put key in shared link
put a name in shared link
add tests
login_pseudo
make PseudoUser work
create a guest user when a link is shared
add BCRYPT_WORKFACTOR to configuration

Closes #62
return pseudo user if it exists
add lint script

Closes #57
restrict annotating for guest users
restrict commenting
Merge branch 'review-link'

Closes #47