Add GUT (CLI only) and remove gd-plug

Commit GUT directly to the git repo and remove gd-plug as it is no
longer required to install GUT.

Modify GUT to be used by command-line only.

For example:
```
cp test/.gutconfig.ci.json .gutconfig.json
godot --no-window -s addons/gut/gut_cmdln.gd
```

addons/gut/parameter_factory.gd

@@ -0,0 +1,75 @@
+# ##############################################################################
+#(G)odot (U)nit (T)est class
+#
+# ##############################################################################
+# The MIT License (MIT)
+# =====================
+#
+# Copyright (c) 2020 Tom "Butch" Wesley
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+#
+# ##############################################################################
+# This is the home for all parameter creation helpers.  These functions should
+# all return an array of values to be used as parameters for parameterized
+# tests.
+# ##############################################################################
+
+# ------------------------------------------------------------------------------
+# Creates an array of dictionaries.  It pairs up the names array with each set
+# of values in values.  If more names than values are specified then the missing
+# values will be filled with nulls.  If more values than names are specified
+# those values will be ignored.
+#
+# Example:
+# 	create_named_parameters(['a', 'b'], [[1, 2], ['one', 'two']]) returns
+#		[{a:1, b:2}, {a:'one', b:'two'}]
+#
+# 	This allows you to increase readability of your parameterized tests:
+#	var params = create_named_parameters(['a', 'b'], [[1, 2], ['one', 'two']])
+#	func test_foo(p = use_parameters(params)):
+#		assert_eq(p.a, p.b)
+#
+# Parameters:
+# 	names:  an array of names to be used as keys in the dictionaries
+#   values:  an array of arrays of values.
+# ------------------------------------------------------------------------------
+static func named_parameters(names, values):
+	var named = []
+	for i in range(values.size()):
+		var entry = {}
+
+		var parray = values[i]
+		if typeof(parray) != TYPE_ARRAY:
+			parray = [values[i]]
+
+		for j in range(names.size()):
+			if j >= parray.size():
+				entry[names[j]] = null
+			else:
+				entry[names[j]] = parray[j]
+		named.append(entry)
+
+	return named
+
+# Additional Helper Ideas
+# * File.  IDK what it would look like.  csv maybe.
+# * Random values within a range?
+# * All int values in a range or add an optioanal step.
+# *