lib/srdb1: clone db url in db_id structure
lib/srdb1: extented DBv1 with async raw query and async insert

- functions that should be executed in async mode
db_mysql: implemented async raw query and async insert

- both use the core async framework
sqlops: new cfg function - sql_query_asycn(con, sql)

- execute sql statement via async raw query, if implemented by db driver
  module (e.g., db_mysql)
- the query is executed in another process and result is not available
  back to config, thus it should be used only for sql statements that
  don't return values (e.g., insert, delete, update...)
sqlops: documentation for sql_query_async()
acc: if db_insert_mode==2, use async db insert to store the record

- the acc record will be stored via async framework if db driver
  implement insert_async()
acc: extended documentation for db_insert_mode parameter

- if set to 2, async insert operation is used to store the acc record in
  database table