.editorconfig

worker: raise exception instead of calling sys.exit() with child's code

When a worker process returns an error code, we would call
`sys.exit()` with that exit code on the main process. The `SystemExit`
exception would then get caught in `scmutil.callcatch()`, which would
return that error code. The comment there says "Commands shouldn't
sys.exit directly", which I agree with. This patch changes it so we
raise a specific exception when a worker fails so we can catch
instead. I think that means that `SystemExit` is now always an
internal error.

(I had earlier thought that this call to `sys.exit()` was from within
the child process until Matt Harbison made me look again, so thanks
for that!)

Differential Revision: https://phab.mercurial-scm.org/D9287

# See http://EditorConfig.org for the specification

root = true

[*.py]
indent_size = 4
indent_style = space
trim_trailing_whitespace = true
end_of_line = lf

[*.{c,h}]
indent_size = 8
indent_style = tab
trim_trailing_whitespace = true
end_of_line = lf

[*.t]
indent_size = 2
indent_style = space
trim_trailing_whitespace = false
end_of_line = lf