Allow serializers to take arrays

At the moment serialization only allows individual objects to be serialized.
Arrays of objects need to be `map`'ed in the endpoint.  This commit changes that
so serialize can take one or many objects of a given type and sort it out so the
endpoint doesn't need to.
Merge pull request #125 from neilmiddleton/better_serializer

Allow serializers to take arrays
Update link to interagent/pliny in README
Merge pull request #129 from mattreduce/patch-1

Update link to interagent/pliny in README
change to use casting config by default
Merge pull request #131 from will/castingconfig

change to use casting config by default
Only enable Rollbar if access token is available
Merge pull request #130 from mattreduce/patch-1

Only enable Rollbar in production
Use Encode helper
Rename RESCUE_ERRORS to RAISE_ERRORS in .env.sample
Merge pull request #132 from interagent/tmaier-encode-2

Use Encode helper
Add application.rb
Merge pull request #133 from interagent/tmaier-app-rb

Add application.rb
set perms of .env to 0600 on init
Merge pull request #134 from chooper/fix-env-perms

set perms of .env to 0600 on init
Clean database before rspec suite running

https://github.com/DatabaseCleaner/database_cleaner#rspec-example
Merge pull request #136 from interagent/tmaier-rspec-db

Clean database before rspec suite running