Integration tests should be run locally before committing code changes

Currently, it is easy to submit a patch for code changes without first running integration tests locally.

Two changes could help with this:

1. Adding this information to documentation for contributors
2. Adding a make task that runs all necessary tasks before contributing new code, which are:

make check-spaces make check make test-network-all

We should investigate how to handle:

• Someone not having have chutney
• Someone not having the necessary network connection for integration tests to succeed
• If chutney tests fail because of flakiness (race conditions for example) rather than legitimate failures.