bump to version 0.3.0
remove Gemfile.lock from .gitignore
field_name option can be called in the can_be block
added pry as a dev dependency
default_type can now be specfied in the block
start the 0.3.0 version in the change log
only build the master branch on travis
Revert "only build the master branch on travis"

This reverts commit d8612ad071bb3b3734f517475edf35e219feda6e.
added change to blocks
the details_name option is now configurable