Fix help target; add keyring help
Makefile:  help, fixes, misc
Add infra convenience target
xenomai make rules:  add convenience target
Linux rules:  add convenience target and help
linux rules:  fix submodule update
linux-tools rules:  fix submodule update
linux rules:  fix renamed submodule
linux-tools rules:  add convenience target and help
libsodium rules:  add convenience target and help
libsodium:  rule to update submodule
zeromq4:  add submodule checkout
zeromq4:  add convenience target and help
libwebsockets:  add submodule checkout rules; add convenience target
jansson: Add convenience torget and submodule update
pyzmq:  add convenience target and submodule checkout
czmq:  add convenience target and submodule checkout
linux-tools submodule updates:  missing Build-Deps
Makefile:  change info-% to util-% pattern; fix chroot util
Tweak ppa configuration