Merge pull request #172 from bepetersn/0.9-beta7

fixes #167; tarbell generate throws a failing exit status if templates don't render
coerce integer values from spreadsheet, closes #181
add preview hook and remove ultimately annoying hook execution print statement, closes #185
Merge pull request #189 from eads/0.9-beta7

Fix integers and add preview hook
wrap puts to in cli.py to detect werkzeug reloader process
refine run server cli copy
put a newline in front of errors
Merge pull request #190 from eads/0.9-beta7

Fix doubled messages due to reloader
allow comma separated email address lists
Merge pull request #192 from eads/0.9-beta7

allow comma separated email address lists
bail if no configuration found
Merge pull request #193 from eads/0.9-beta7

bail if no configuration found
should exit with error code
Merge pull request #194 from eads/0.9-beta7

should exit with error code
make sure everything is utf-8
clean up context processor imports
remove unused code and silly 'black' function
use gnu readline
remove docs stuff, only devs need it
Merge pull request #195 from eads/0.9-beta7

Fix line overflow issues, hypothetically fixes #121 for good.