Raise if giving non-keywords to Keyword
Provide Mix.raise/1 that attaches mix info to Mix exceptions

Closes #1744
Define Mix.Config
Use new Mix.Config in generated files
Improve formatting
enable passing --names to `mix help` to only display command names
combine loops
add test for `mix help --names`
Merge pull request #2361 from pwoolcoc/mix-help-names

Mix help names
Fix typo on CLI --app parsing
Document the additional `--names` argument that `mix help` can take
Merge pull request #2364 from pwoolcoc/minor-mix-help-fix

Document the additional `--names` argument that `mix help` can take
Add missing |> Stream.run/1 to its documentation
Add guard to impl of Enumerable for Function

This improves the stacktrace in case of wrong dispatch.
Revert "Set up the monitor only on await for tasks"

This reverts commit 85a04fe919741c38ed00fbb8380a324ddb79aa0e.
Do not catch failures on tasks

Closes #2345
Merge pull request #2350 from ericmj/keyword-error

Raise if giving non-keywords to Keyword
Add a CHANGELOG entry to task change
Revert "EEx tests aware of CR+LF newline on Windows"

This reverts commit f60d3668eda292e6451a059a20f28cb71ce2c0b7.
Fix :io.columns calls