Implement Cobra CLI tooling, Viper config tooling (#336)

* start pulling out + replacing urfave and config

* replace many many instances of config

* move more stuff => viper

* properly remove urfave

* move some flags to root command

* add testrig commands to root

* alias config file keys

* start adding cli parsing tests

* reorder viper init

* remove config path alias

* fmt

* change config file keys to non-nested

* we're more or less in business now

* tidy up the common func

* go fmt

* get tests passing again

* add note about the cliparsing tests

* reorganize

* update docs with changes

* structure cmd dir better

* rename + move some files around

* fix dangling comma

vendor/github.com/subosito/gotenv/CHANGELOG.md

@@ -0,0 +1,47 @@
+# Changelog
+
+## [1.2.0] - 2019-08-03
+
+### Added
+
+- Add `Must` helper to raise an error as panic. It can be used with `Load` and `OverLoad`.
+- Add more tests to be 100% coverage.
+- Add CHANGELOG
+- Add more OS for the test: OSX and Windows
+
+### Changed
+
+- Reduce complexity and improve source code for having `A+` score in [goreportcard](https://goreportcard.com/report/github.com/subosito/gotenv).
+- Updated README with mentions to all available functions
+
+### Removed
+
+- Remove `ErrFormat`
+- Remove `MustLoad` and `MustOverload`, replaced with `Must` helper.
+
+## [1.1.1] - 2018-06-05
+
+### Changed
+
+- Replace `os.Getenv` with `os.LookupEnv` to ensure that the environment variable is not set, by [radding](https://github.com/radding)
+
+## [1.1.0] - 2017-03-20
+
+### Added
+
+- Supports carriage return in env
+- Handle files with UTF-8 BOM 
+
+### Changed
+
+- Whitespace handling
+
+### Fixed
+
+- Incorrect variable expansion
+- Handling escaped '$' characters
+
+## [1.0.0] - 2014-10-05
+
+First stable release.
+