Display nice fail page if someone looks for a podcast, that is not in database.

fixes #73
closes #73
more general error message
Merge branch 'tmp' into dev
update gems to prepare for advanced testing
Merge branch 'master' into dev
show 404 if podcast info page could not be found
cleanup routes newlines
generate rspec install
remove rails default tests
customize some rspec settings and add auto test case generation for scaffolding
add some first podcast model rspec tests
complete simple tests
more simple validtion test
tests can be written more simple this way
test index info model
add new unimplemented tests to podcasts model
implement all test cases and add context to cluster some test cases
try to automate testing with travis ci
only build master and dev branch
comment these test. user experience with these restionctions very bad