Add a new program, loadtest, that runs a requested number of client sessions
in parallel to a loolwsd server. A client session loads one of a list of test
documents, and does some operations on it.
Move the getTokenInteger() and getTokenString() functions out from LOOLSession
into a new namespace LOOLProtocol, as they are neeeded also in the loadtest
program.
Add, also in LOOLProtocol, functions to parse some of the messages from the
server. (In general that is done in client JavaScript code, of course; only
for testing purposes needed in C++ code.)
For now, each LOOL client has a separate child process (or none at all, if it
has accessed only information found in the cache). This will obviously have to
chnage to handle collaboration. Etc.
The parent process talks the same Websocket protocol with the child
processes. When there is a child process for a client, traffic from the client
is forwarded as such to the child process and vice versa.
Will be needed if we want loolwsd to run on Windows. Then we will have one
process receiving the connections from WebSocket clients and sending the
accepted connection sockets to child processes thatr might be already running,
either because they have been "pre-forked", or because of a collaboration
scenario where new clients join a session working on a document.
But initially we will write this as if for Unix only, so development of this
migratory socket stuff is paused for now. (And it isn't even clear whether the
API design so far is a good idea and elegantly implementable.)
