lfs: handle URLErrors to add additional information
Sometimes the blob server is hit first (e.g. on push), and sometimes it's hit
last (e.g. pull). Throw in depth first subrepo operations, and things quickly
get insane. It wasn't even mentioning LFS, so just saying "connection refused"
can be confusing- especially if the blob server is a secondary server and
connecting to the repo server works.
The exception handler for the transfer handler will print the full path to the
blob, but that seems fine given that it might be necessary to debug a second
server. (We don't yet support a standalone blob server, so the handler for the
Batch API will cover 99.9% of the current problems. But it might as well be
handled now while I'm thinking about it.)
The function for translating to a message was mostly borrowed from
scmutil.catchall().
syntax: glob
*.elc
*.tmp
*.orig
*.rej
*~
*.mergebackup
*.o
*.so
*.dll
*.exe
*.pyd
*.pyc
*.pyo
*$py.class
*.swp
*.prof
*.zip
\#*\#
.\#*
tests/artifacts/cache/big-file-churn.hg
tests/.coverage*
tests/.testtimes*
tests/.hypothesis
tests/hypothesis-generated
tests/annotated
tests/exceptions
tests/*.err
tests/htmlcov
build
contrib/chg/chg
contrib/hgsh/hgsh
contrib/vagrant/.vagrant
dist
packages
doc/common.txt
doc/*.[0-9]
doc/*.[0-9].txt
doc/*.[0-9].gendoc.txt
doc/*.[0-9].{x,ht}ml
MANIFEST
MANIFEST.in
patches
mercurial/__modulepolicy__.py
mercurial/__version__.py
mercurial/hgpythonlib.h
mercurial.egg-info
.DS_Store
tags
cscope.*
.idea/*
.asv/*
i18n/hg.pot
locale/*/LC_MESSAGES/hg.mo
hgext/__index__.py
rust/target/
rust/*/target/
# Generated wheels
wheelhouse/
syntax: regexp
^\.pc/
^\.(pydev)?project
# hackable windows distribution additions
^hg-python
^hg.py$