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/magiconair/properties/rangecheck.go

@@ -0,0 +1,31 @@
+// Copyright 2018 Frank Schroeder. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package properties
+
+import (
+	"fmt"
+	"math"
+)
+
+// make this a var to overwrite it in a test
+var is32Bit = ^uint(0) == math.MaxUint32
+
+// intRangeCheck checks if the value fits into the int type and
+// panics if it does not.
+func intRangeCheck(key string, v int64) int {
+	if is32Bit && (v < math.MinInt32 || v > math.MaxInt32) {
+		panic(fmt.Sprintf("Value %d for key %s out of range", v, key))
+	}
+	return int(v)
+}
+
+// uintRangeCheck checks if the value fits into the uint type and
+// panics if it does not.
+func uintRangeCheck(key string, v uint64) uint {
+	if is32Bit && v > math.MaxUint32 {
+		panic(fmt.Sprintf("Value %d for key %s out of range", v, key))
+	}
+	return uint(v)
+}