Remove patch from debian files

Including bionic build fix
Don't know why focal worked without it

per Debian manual, extra is deprecated and means the same thing as optional
https://www.debian.org/doc/debian-policy/ch-archive.html#s-priorities

to libjsp-api-java and libservlet-api-java
and update symbolic links to the jars in /usr/share/java
Note that the previous symlink to servlet-api-3.1.jar was
another symlink to servlet-api.jar which was actually API 4 anyway.

to avoid conflict in applications linking to apache jars
As requested by 'mesh' project
Remove with-libhttpclient-java build option
No known external uses other than obsolete i2pcontrol plugin

libjetty9-java used to depend on libservlet3.1-java
but now in sid it doesn't.
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=997213

Source remains for now and may still be built with ant buildBOB.
Existing non-package installs will continue to work.

fix a lintian warning about compare-versions
update launchpad doc for git

Fix build error dh_installdocs linking from the libjbigi-jni arch package
to an arch:all package, this is an error for compat level 10.

checklist updates

Eepsite: pull new and updated help translations

Replace possibly more-translated, but very very old (not from transifex) pages

refresh patches
update release docs

Ant version 1.9.8 or higher now required
Drop support for Xenial package build
Fix up BOB build configuration
Fix i2psnark standalone build

Switch Bionic to 9.x
Disco+ already on 9.x
Xenial remains on 8.x
Update dependencies doc

Bundle 2.0 API only; remove 1.1 API
Convert DoH, NDT, and i2pcontrol to the 2.x API
Fix i2pcontrol handling of number values and serialization for 2.x API
Remove xenial dependency on libjson-simple-java, it has only 1.1
Set min and max version constraint on libjson-simple-java for bionic+
Based on patch from Gilles Filippini
ref: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=901827
This does not support 3.x but the patch for that will be smaller.

Add xenial patch to ant test target

Jetty 9.3.28 (ticket #2098)
This breaks Debian builds, fixes to follow