Fix crash or hang when shutting down a websocket server

[abitmore]

Changes in this pull request:

• bumps FC to include changes made in Websocket code refactory and bugfix bitshares-fc#201, and
• remove no longer needed sleeps in cli_tests.

For issue #1784 and #1856.

Update: the FC bump closes #2197 by the way.

[abitmore]

With this patch, cli_test occasionally hang after finished running test case cli_quit, with following error message

Testing wallet connection and quit command.
1435490ms th_a       wallet_api_impl.cpp:168       quit                 ] Quitting Cli Wallet ...
/bts/tests/cli/main.cpp(364): info: check 'exception fc::canceled_exception is caught' passed
Cleanup cli_wallet::boost_fixture_test_case
1435491ms th_a       db_management.cpp:243         close                ] Rewinding from 0 to 0
1435513ms th_a       database_api.cpp:91           ~database_api_impl   ] freeing database api 163935040
1435513ms th_a       database_api.cpp:91           ~database_api_impl   ] freeing database api 163975424
1435513ms th_a       database_api.cpp:91           ~database_api_impl   ] freeing database api 163986128
1435513ms th_a       database_api.cpp:91           ~database_api_impl   ] freeing database api 163970032
1435513ms th_a       database_api.cpp:91           ~database_api_impl   ] freeing database api 163978432
1435514ms p2p        thread.cpp:258                exec                 ] thread canceled: 9 canceled_exception: Canceled

    {}
    p2p  thread_d.hpp:493 start_next_fiber
unknown location(0): fatal error in "cli_quit": memory access violation at address: 0x00000000: no mapping at fault address
/bts/tests/cli/main.cpp(364): last checkpoint
Test is aborted
Leaving test case "cli_quit"; testing time: 64241mks
Leaving test suite "Test Application"

*** 1 failure detected in test suite "Test Application"

or no message at all

Testing wallet connection and quit command.
1062625ms th_a       wallet_api_impl.cpp:168       quit                 ] Quitting Cli Wallet ...
/bts/tests/cli/main.cpp(364): info: check 'exception fc::canceled_exception is caught' passed
Cleanup cli_wallet::boost_fixture_test_case
1062626ms th_a       db_management.cpp:243         close                ] Rewinding from 0 to 0
1062645ms th_a       database_api.cpp:91           ~database_api_impl   ] freeing database api 160498176
1062645ms th_a       database_api.cpp:91           ~database_api_impl   ] freeing database api 160538688
1062645ms th_a       database_api.cpp:91           ~database_api_impl   ] freeing database api 160549264
1062645ms th_a       database_api.cpp:91           ~database_api_impl   ] freeing database api 160533296
1062645ms th_a       database_api.cpp:91           ~database_api_impl   ] freeing database api 160541696
1062646ms p2p        thread.cpp:258                exec                 ] thread canceled: 9 canceled_exception: Canceled

    {}
    p2p  thread_d.hpp:493 start_next_fiber

[abitmore]

I tried to replace canceled_exception with a new exception but cli_test still occasionally hangs after the cli_quit test case. I guess the issue is related to exception handling in task management in FC. I'll stop working on this so far and create a new issue (update: created issue #2205) since I think it is out of scope.

Testing wallet connection and quit command.
226674ms th_a       wallet_api_impl.cpp:168       quit                 ] Quitting Cli Wallet ...
/bts/tests/cli/main.cpp(364): info: check 'exception fc::cli_quit_exception is caught' passed
Cleanup cli_wallet::boost_fixture_test_case
226675ms th_a       db_management.cpp:243         close                ] Rewinding from 0 to 0
226699ms th_a       database_api.cpp:91           ~database_api_impl   ] freeing database api 146940560
226700ms th_a       database_api.cpp:91           ~database_api_impl   ] freeing database api 146981072
226700ms th_a       database_api.cpp:91           ~database_api_impl   ] freeing database api 146991648
226701ms th_a       database_api.cpp:91           ~database_api_impl   ] freeing database api 146975680
226701ms th_a       database_api.cpp:91           ~database_api_impl   ] freeing database api 146984080
226702ms p2p        thread.cpp:258                exec                 ] thread canceled: 9 canceled_exception: Canceled

    {}
    p2p  thread_d.hpp:493 start_next_fiber
unknown location(0): fatal error in "cli_quit": memory access violation at address: 0x00000000: no mapping at fault address
/bts/tests/cli/main.cpp(364): last checkpoint
Test is aborted
Leaving test case "cli_quit"; testing time: 71191mks
Leaving test suite "Test Application"

*** 1 failure detected in test suite "Test Application"