Added specific error types rather than generic error types
Merge pull request #41 from JalfResi/error-types

Added specific error types rather than generic error types
Added check to ensure that period is found in version string of RSS node
Merge pull request #42 from JalfResi/bugfix/rss-node-missing-version

Added check to ensure that period is found in version string of RSS node
Added interfaces and changes to decouple the database implementation from the feed. Should simplify swapping out concrete implementations of database
Merge branch 'database' of https://github.com/JalfResi/go-pkg-rss into database