use a containsKey()+put instead of putIfAbsent because putIfAbsent is not present in Java 8, thereby breaking Maven builds

Can't get the icons to look nice

Quote and shellcheck the jbigi.jar build scripts in order to fix errors when building jbigi jars on Windows

Change the gmp mirror so that when you try to build a jbigi.jar it does not fail. Can be changed back by editing core/c/jbigi/download_gmp.sh

Set limit to 0 if vmCommSystem
i2ptunnel: Do not retry if session limit exceeded

bump BuildTime

Strip file:// in create form for non-JS DnD
Add IDs to relevant elements for access by JS
JS to follow after further testing

Doesn't really do much yet because none of our js has jsdocs

preliminary in case TX API v2 stops working

for a large number torrents
ref: http://zzz.i2p/topics/3475

to improve text readability.
Remove post-render CSS modification of graph images

Contains code adapted from I2P+. License:
Permission is granted to upstream to incorporate I2P+ modifications under the license
of the applicable upstream subsystem as specified in LICENSE.txt.

Console: Fix dark theme CSS color tweak affecting more than the intended inbound.png and outbound.png images

unintended side-effect of CSS tweak in last release

Moved from NetDbRenderer
Use in CLI only for now
CLI and conversion micro-optimizations

only if configured for 6 or more tunnels

Reported on Windows 10
ref: http://zzz.i2p/topics/3500

This will probably also reduce builds at startup.
Limits may require tweaks after further testing.

Never let SSU1 test result be symmetric NAT, it's probably charlie
Don't use SSU1 test if we think we are symmetric NAT
Cleanup two places to call new fail() method

- Send msg 6 even if msg 5 is not received, after a short delay, to detect symmetric NAT
- Prevent test result of symmetric NAT if Charlie is the one that appears to be symmetric natted.
- Mark if Charlie unreachable if apparently symmetric natted.
- Do not treat a different IP but same port as symmetric NAT
- Increase msg 6 retransmission frequency
- Ignore msg 5 received after sending msg 6
- Call externalAddressReceived() on reception of msg 7
- Add javadoc for testComplete() state machine

Most changes only affect SSU2; some SSU1 changes to follow.

ref: http://zzz.i2p/topics/3489

Rename isSnatted() to isSymNatted()
Minor rewrite in PeerState2.gotTermination()
Remove dead peer when pinging fails in intro manager
Cleanup ip length check in externalAddressReceived()
Log tweaks