GetAllLines method will initiate retrieval of headers
and few lines of message text, for all messages from the
server. wodPop3 will loop through all messages, until all
headers and lines for all messages are not received. Once
it finishes, it will fire Done event.
After each message are received, Received event
will be fired as well - so you can inspect headers and text
content immediately (or you can do it later on, depends on
your choice).
During transfer of the headers, Progress event
will be fired. It will contain invalid Total argument,
because Total specifies size of the message - not size of
headers.
No files are created on local disk when this method is
used - all content is kept in memory.