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/inconshreveable/mousetrap/README.md

@@ -0,0 +1,23 @@
+# mousetrap
+
+mousetrap is a tiny library that answers a single question.
+
+On a Windows machine, was the process invoked by someone double clicking on
+the executable file while browsing in explorer?
+
+### Motivation
+
+Windows developers unfamiliar with command line tools will often "double-click"
+the executable for a tool. Because most CLI tools print the help and then exit
+when invoked without arguments, this is often very frustrating for those users.
+
+mousetrap provides a way to detect these invocations so that you can provide
+more helpful behavior and instructions on how to run the CLI tool. To see what
+this looks like, both from an organizational and a technical perspective, see
+https://inconshreveable.com/09-09-2014/sweat-the-small-stuff/
+
+### The interface
+
+The library exposes a single interface:
+
+    func StartedByExplorer() (bool)