Issue #23
Added more debug lines
Added debugging type PROXY_DEBUG_MYSQL_CONNPOOL
Flag -d can accept a integer value that become the default logging verbosity using init_debug_struct_from_cmdline()
Issue #14
Added pthread_mutex_t GloVars.global.start_mutex
mutex locked by Admin module if nostart is on
mutex released by Admin when issued PROXYSQL START
main() blocks until the mutex is locked

Issue #23
Fixed a bug that was always assigning GloVars.global.gdbg=true

Issue #53
Drafted a basic Standard_ProxySQL_Admin::send_MySQL_OK(MySQL_Protocol *myprot)

Issue #56
If verbosity is greater than 10 , proxy_debug_func() prints backtrace calling:
- backtrace
- backtrace_symbols
- abi::__cxa_demangle