Vk-sdk

- [=] Every class now can behave like Thread class
- [=] thread.threaded - add this decorator to execute function in a thread
- [=] thread.requires_start - wait until bot will be started and execute function
- [+] after keyword to user.write: set after func after write
- [=] Replace: ThreadedStruct and ThreadedDatabase with more elegant threading solution
- [=] ListExtension.join(separator, prefix, postix) - same behaviour as separator.join(Iterable)
- [=] Rewrite Struct
- [+] events
- [+] setExtension - += operation for sets

- [+] Autocreate path for database
- [+] Use relative imports
- [+] jsonExtension.load(file) -> jsonExtension.load(file, ident) for pretty json output later
- [+] StructByAction is now iterable

- [+] one_time parameter to ThreadedStruct constructor: don't cache created database in thread manager
- [+] one_time parameter to ThreadedDatabase constructor: -//-
- [=] Don't pass arguments to function, created by command decarator if function doesn't accept any
- [=] User class now caches avatar and user name on create
- [=] User class can be None if provided user_id is invalid
- [+] ListExtension.all: returns True, if function(item) returns True for all items in list

- [-] db.tasks
- [+] tasks to all threads

- [=] Start on adding versions
- [=] changed all Structs constructors (MyStruct(self.db, param1=param) -> MyStruct(param1=param))
- [+] ThreadedDatabase.select_one_struct
- [+] ThreadedDatabase.select_all_structs
- [+] ThreadedStruct