define_method rather than having separate instance variables for each attribute. Spec
clearer name
fix visibility param
use self.class so inheritance can override
no longer need to write the attributes through method, we have access through attributes hash
convert incoming hash keys to strings to avoid losing attributes by letting them be symbols
helpers for checking object persistence
variable use consistency
Merge pull request #8 from jphenow/synchronize-attributes-hash

define_method rather than having separate instance variables for each at...