Use ATOM_HOME env var in protocol handler

Closes atom#5501

Update cursors as soon as all required measurements are assigned

Merge pull request atom#5368 from atom/ld-jasmine-ref-fix

Fix link to wrong version of Jasmine

Merge pull request atom#5235 from atom/atom-shell-v0.20.7

Upgrade to atom-shell v0.20.7

⬆️ apm@0.123

Merge pull request atom#4169 from atom/upgrading-docs

Add package upgrade guide

⬆️ markdown-preview

⬆️ season@5.0.5

⬆️ autocomplete@0.42

For inclusion of completions from all matching scopes

⬆️ language-python@0.30