Add methods; export functions and classes

* Add TLabApplication::mainFile and TLabApplication::files files methods
* Add TEditLabRequestData::setId method
* Export friend operators
* Export TGetUserConnectionInfoListReplyData and TServerState
Fix

* Improve TAddLabRequestData and TEditLabRequestData validity checking
Add TLabInfo::size method
Fix TNetworkClient operation autodeletion
TeXSample v2.1.0

* Improve TAddLabRequestData/TEditLabRequestData validity checking
* Fix TNetworkClient operation autodeletion
* Add TLabApplication::mainFile and TLabApplication::files files methods
* Add TEditLabRequestData::setId method
* Add TLabInfo::size method
* Export friend operators
* Export TGetUserConnectionInfoListReplyData and TServerState
TeXSample v2.1.0

* Improve TAddLabRequestData/TEditLabRequestData validity checking
* Fix TNetworkClient operation autodeletion
* Add TLabApplication::mainFile and TLabApplication::files files methods
* Add TEditLabRequestData::setId method
* Add TLabInfo::size method
* Export friend operators
* Export TGetUserConnectionInfoListReplyData and TServerState