The changes are mostly done via `xo --fix`; the other changes are
either trivial or disabling new linter rules that we plan to address
in future commits.
Using `import * as` import syntax causes some problem if the
module exports a class or function. Because the whole point of
star import is to import every property the module exports. It turns
out we have been using it incorrectly in many places which this commit
fixes.
Then we fix a linting error by adding a eslint disable rule to solve
it along with a TODO because the way we currently do it is wrong.
Finally, to conclude this cleanup, we merge all the .gitignore paths
into once now that we can.
