dos -> unix; add logging; escape chars in mat2json

I suspect the webserver code was written in a Windows environment; all
the files were dos encoded. fixed.

I added logging capabilities in webserver. probably there should be some
scrubbing of the log directory. (ack!)

I added proper escaping of 'bad' characters in mat2json. there should be
similar conversions, I am guessing, in json2mat.
logging in webserver, fix json escapes

robustifying webserver with try/catch blocks and some logging capabilities.

fixing bad character escapes in mat2json so stdout is converted to valid JSON.
adding test cases of same in test.py.

re-encoding utilities dos -> unix.
ignore log directory generated by testing.

a www/log directory is created to hold webserver logs; ignore these in git.
adding timeout to webserver

after discovering a bunch of zombie webservers still running, I've added a
timeout option (inf for b/w compatibility), along with a sentinel file.
explicit termination via http://localhost:portnum/exit.m

Instead of relying on www/exit_server.m which kills matlab without the proper
cleanup, add a wart where http://localhost:port/exit.m is a 'speical' webpage
that signals webserver to shut down cleanly.
missing semicolons
various fixes

adding static 404 and favicon; for testing in a browser.
there should be a dynamic 404.

mat2json: fields is an error, should be fieldnames.
the shutdown is exit.m, not exit_server.m