* Make it possible to explicitly disable discovery
Discovery will be disabled in following cases:
- if there are not bootnodes - v5 server will be disabled
because there is no point in running it
- if user defined in config NoDiscovery=true this value will be preserved
even if we have bootnodes
So, basically discovery will be always enabled by default on mobile, unless
it is explicitly specified otherwise.
When statusd is used current behavior is that discovery is disabled by default.
I kept it in this change, but it would be better to change it.
* Fix leftovers
* Add wait group to peer pool to protect from races with p2p.Server
* Change fields only when all goroutines finished
* Turn off discovery after topic searches are stopped
* Don't set period to nil to avoid race with SearchTopic
* Close period chan only when all writers are finished
* Add default peer limits configuration
If discovery is enabled for a given cluster - we will set a default
expected number of peers for each enabled service. For example:
- if cluster is rinkeby has a discovery enabled we will
check which services are enabled
- if whisper is enabled we will set min and max limits by default
- if les is enabled and infura is not used we will set limits too
When statusd is used - configuration must be provided using configuration
supported by statusd.
* Fix deadlock in les peer set
Dmitry Shulyak