common, core, light: add block age into info logs

Interpreter initialization is left to the PRs implementing them.
Options for external interpreters are passed after a colon in the
`--vm.ewasm` and `--vm.evm` switches.

* Bugfix #17216: evm loads prestate file properly now

* code gofmted

* swarm: fixed comment typo
* eth: fixed comment typo
* cmd/puppeth: fixed comment typo

The argument is inclusive rather than exclusive, according to docs.

travis, Dockerfile, appveyor, build: bump to Go 1.11

* abi,signer: fix nil dereference in #17633

* signer/core: tiny typo fix in test error message

* ethdb: unified code comment style.

* puppeth: it is unnecessary to alloc pre-funded to 256 addresses

* Revert "puppeth: it is unnecessary to alloc pre-funded to 256 addresses"

This reverts commit 5e04fbccf0b8aca85030af1779bb7a949033d9d8.

* puppeth: fix comment typo

* Revert "ethdb: unified code comment style."

This reverts commit a581efb3f06a96fc7aec0bfae03c7b6d5a0c1a77.

* cmd/puppeth: fix comment typo

* swarm/network: Protocol bump (for chunk refactor)

* swarm/network: Increase discovery and stream protocol version too

* swarm/network: Increase priority queue cap

Eip1234

* ethdb: unified code comment style.

* puppeth: it is unnecessary to alloc pre-funded to 256 addresses

* Revert "puppeth: it is unnecessary to alloc pre-funded to 256 addresses"

This reverts commit 5e04fbccf0b8aca85030af1779bb7a949033d9d8.

* puppeth: fix comment typo

* Revert "ethdb: unified code comment style."

This reverts commit a581efb3f06a96fc7aec0bfae03c7b6d5a0c1a77.

 consensus/clique, core: chain maker clique + error tests

README: Change gitter badge to discord

cmd/clef: fix incorrect file permissions for secrets.dat

Co-authored-by: Janos Guljas <janos@resenje.org>
Co-authored-by: Balint Gabor <balint.g@gmail.com>
Co-authored-by: Anton Evangelatov <anton.evangelatov@gmail.com>
Co-authored-by: Viktor Trón <viktor.tron@gmail.com>

* swarm/storage: remove redundant increments for dataIdx and entryCnt

* swarm/storage: add Delete to LDBStore

* swarm/storage: wait for garbage collection

* swarm/network: simplify kademlia/hive; rid interfaces

* swarm, swarm/network/stream, swarm/netork/simulations,, swarm/pss: adapt to new Kad API

* swarm/network: minor changes re review; add missing lock to NeighbourhoodDepthC

cmd/swarm: password threw on upload manifest

Signed-off-by: YaoZengzeng <yaozengzeng@zju.edu.cn>