Cosmos-sdk: Move out modules unit tests from basecoin

[rigelrozanski]

There are a number of handler tests which test specific functionality of handlers within app_test.go in the basecoin examples (and now duplicated in cmd/gaia) - The reason for this is that the tests require some kind of full application to be performed, baseapp is a full application. In reality we should move these full application tests back into each of the modules and have some common full-application constructor in tests/ which each of the modules tests can call to recreate that "I'm in the basecoin application" feel. @ebuchman @mossid @cwgoes

[cwgoes]

Can this be combined with the functionality in mock, which looks like it serves a similar purpose (for a simple key-value store app)?

[rigelrozanski]

Yeah I think that makes sense, could be a good place for that code to live

[rigelrozanski]

I think we could include the sequence testing as a part of this issue when we address this https://github.com/cosmos/cosmos-sdk/pull/812#issuecomment-380043230

[ebuchman]

Looks like this was done