make sure indexes are only created for types with unique attrs
no need to check is_indexable
extra docstring
check for more specific error (when missing index)
keep py2neo on v1.5 for now
extra test for create type with no unique attrs
travis build for py2neo 1.6.3 as well as default
fix to travis.yml
travis fix
bump version and add changes
Merge pull request #105 from onefinestay/create_type_should_not_always_create_index

Indexes are only created for types with unique attrs