Block test improvements

Remove "minGasPrice" field from JSON responses. Closes. #754

trivial fix for: Broken link for detailed go build instructions #661

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admin.StopRPC added to console

cmd/geth, cmd/utils: add cli flags for pprof and whisper

Merge branch 'frontier/natspec' of https://github.com/ethersphere/go-ethereum into ethersphere-frontier/natspec

* Add fixes to parsing and converting of fields in tx tests
* Correct logic in tx tests; validation of fields and correct
  logic for when RLP decoding works/fails and when this is
  expected or not
* Rename files for consistency
* Add block tests wrapper to run block tests with go test

- simplify resolver and tests
- added missing test for KeyToUrl
- fix notice error message and its test with !%x(MISSING)
- natspec test: insertTx modified - does not prepend 0x to contract address
- disable networking in e2e test