Fix spec for surround_many
Fix :stderr_to_stdout option
Send elixir version as parameter when installing hex
Make some docs more gender neutral
Merge pull request #2796 from pdericson/gender

Make some docs more gender neutral
Give higher prio to powershell on windows
Fix documentation of IO module
Merge pull request #2803 from dskecse/fix-io-docs

Fix documentation of IO module