Squashed 'floo/common/' changes from 39819ce..f264cce

f264cce Parse lazy workspace URLs that don't include the domain.
001b45c Fix occasional keyerror when uploading.
216861a IGNORE_MODIFIED_EVENTS is never used.
808933b Don't send None.
f88dfa0 Add req_id/res_id support.
170da1d Don't md5sum twice. Mention if there was an error calculating checksums for a buffer. Add more logging to on_patch.

git-subtree-dir: floo/common
git-subtree-split: f264cced5c7d99538de5a19509db00ab3927e257
Merge commit 'fa0394737072b20c1f2e36b871af60cf8d3153f7'
Bump version.