RPC: Exclude PUT requests from pending requests

- Exclude PUT requests made by perun-engine from pending requests, since
  they contain a lot of data (listing / getData queries).
- TTL for pending requests lowered to 1 minute.
Merge pull request #626 from zlamalp/put

RPC: Exclude PUT requests from pending requests
GUI: fixed display of sync of interval on groups
Merge pull request #627 from zlamalp/fix

GUI: fixed display of sync of interval on groups