Updating bottle_sqlite.py to new bottle

Updating bottle_sqlite.py to new bottle versions
inspired by bottle_sqlalchemy
adapted to python3
sqlalchemy->sqlite

Correct a bad copy-paste
change sqlalchemy keyword to sqlite
correct keyword in args

correct bad copy-paste to not change this plugin behavior
Set plugin api=2 to make it work with older bottle versions.
Add .gitignore, tox and travis files.