Merge pull request #43 from JohnSundell/process-inject

Enable a custom Process instance to be injected

Merge pull request #23 from SteveBarnegren/dont_close_standard_file_h…

…andlers

Don't close standard file handlers

Merge pull request #40 from hisaac/master

Update to Swift 4.2

Merge pull request #25 from harlanhaskins/on-your-mark-get-set-go

Synchronize reads/writes to outputData and errorData

README: Recommend using HTTPS to add ShellOut to Marathon

Merge pull request #7 from JohnSundell/linux-fix

Fix build errors on Linux

README: Add instructions for pre-defined commands

README: Update for new series of commands + path API

Make ShellOutError members public