replace out.write(buf.toString) with out.append(buf)
to eliminate extra copy and object churn

i2ptunnel: set bulk profile for servers;
i2psnark: set bulk profile;
Prep for tunnel bw params (proposal 168)

to make the choke/unchoke cycles a little faster

Tweaks to previous MR:
_ Use new constructor for edit CLI
- Javadocs for new constructor
- Add new_url_list param to new constructor
- Set creation date if unset

per user request

to improve search for non-ASCII strings.
Normalize both search and searched strings to NFKD when searching.
NFKD is best because it is more efficient than NFKC and it removes
formatting distinctions. This results in the best fuzzy matching.

i2psnark: Fix config page showing router limit instead of configured i2psnark limit for max up bw after restart (Github #75)

This was just a display issue; actual internal limit was correct.
Snark limit will continue to be capped at about 60% of the router limit
to account for overhead.

these are output by getopt in error messages

by only sending new peers, as in ut_pex.
Track connected time and last pex sent time, and only send
peers connected since the last sent time.
Usually, there are no new peers, so now we don't send a message at all.
Also, don't send PEX to seeds after the handshake.

as reported by mrt
improve error message

as requested

Delete all torrents except magnets when changing data dir

to avoid intermittent "Unable to connect to I2P" message at startup.