* improved error messages in CConcSession::GetTokensFromStorageByBreak(), CConcSession::GetFileSnippets()
- was: concord_daemon_log("Error! Cannot read hit no %i \n", BreakNo); return false;
- now: throw CExpc(errReadSourceFile, "CConcSession::... cannot read $%s storage data for break #%i")
* improved error reporting in CDDCBranchServer::GetHitContexts()
- truncated *._storage_Token file was giving unhelpful legacy "\x{01}cannot read a source file" message
- new code trims \001 separator and prepends subcorpus identifier
* removed error return clauses in CConcSession::GetHits(): now just re-throw exceptions (they should now be caught higher up)