auth: OpenID/OAUth2 middleware

2 configurations for the listeners are now possible:
- enableJWT=false with client ssl auth
- enableJWT=true with https

Actual verification of the tokens is handled by
https://github.com/openshift-online/ocm-sdk-go.

An authentication handler is run as the top level handler, before any
routing is done. Routes which do not require authentication should be
listed as exceptions.

Authentication can be restricted using an ACL file which allows
filtering based on JWT claims. For more information see the inline
comments in ocm-sdk/authentication.

As an added quirk the `-v` flag for the osbuild-composer executable was
changed to `-verbose` to avoid flag collision with glog which declares
the `-v` flag in the package `init()` function. The ocm-sdk depends on
glog and pulls it in.

vendor/github.com/json-iterator/go/reflect_optional.go

@@ -0,0 +1,129 @@
+package jsoniter
+
+import (
+	"github.com/modern-go/reflect2"
+	"unsafe"
+)
+
+func decoderOfOptional(ctx *ctx, typ reflect2.Type) ValDecoder {
+	ptrType := typ.(*reflect2.UnsafePtrType)
+	elemType := ptrType.Elem()
+	decoder := decoderOfType(ctx, elemType)
+	return &OptionalDecoder{elemType, decoder}
+}
+
+func encoderOfOptional(ctx *ctx, typ reflect2.Type) ValEncoder {
+	ptrType := typ.(*reflect2.UnsafePtrType)
+	elemType := ptrType.Elem()
+	elemEncoder := encoderOfType(ctx, elemType)
+	encoder := &OptionalEncoder{elemEncoder}
+	return encoder
+}
+
+type OptionalDecoder struct {
+	ValueType    reflect2.Type
+	ValueDecoder ValDecoder
+}
+
+func (decoder *OptionalDecoder) Decode(ptr unsafe.Pointer, iter *Iterator) {
+	if iter.ReadNil() {
+		*((*unsafe.Pointer)(ptr)) = nil
+	} else {
+		if *((*unsafe.Pointer)(ptr)) == nil {
+			//pointer to null, we have to allocate memory to hold the value
+			newPtr := decoder.ValueType.UnsafeNew()
+			decoder.ValueDecoder.Decode(newPtr, iter)
+			*((*unsafe.Pointer)(ptr)) = newPtr
+		} else {
+			//reuse existing instance
+			decoder.ValueDecoder.Decode(*((*unsafe.Pointer)(ptr)), iter)
+		}
+	}
+}
+
+type dereferenceDecoder struct {
+	// only to deference a pointer
+	valueType    reflect2.Type
+	valueDecoder ValDecoder
+}
+
+func (decoder *dereferenceDecoder) Decode(ptr unsafe.Pointer, iter *Iterator) {
+	if *((*unsafe.Pointer)(ptr)) == nil {
+		//pointer to null, we have to allocate memory to hold the value
+		newPtr := decoder.valueType.UnsafeNew()
+		decoder.valueDecoder.Decode(newPtr, iter)
+		*((*unsafe.Pointer)(ptr)) = newPtr
+	} else {
+		//reuse existing instance
+		decoder.valueDecoder.Decode(*((*unsafe.Pointer)(ptr)), iter)
+	}
+}
+
+type OptionalEncoder struct {
+	ValueEncoder ValEncoder
+}
+
+func (encoder *OptionalEncoder) Encode(ptr unsafe.Pointer, stream *Stream) {
+	if *((*unsafe.Pointer)(ptr)) == nil {
+		stream.WriteNil()
+	} else {
+		encoder.ValueEncoder.Encode(*((*unsafe.Pointer)(ptr)), stream)
+	}
+}
+
+func (encoder *OptionalEncoder) IsEmpty(ptr unsafe.Pointer) bool {
+	return *((*unsafe.Pointer)(ptr)) == nil
+}
+
+type dereferenceEncoder struct {
+	ValueEncoder ValEncoder
+}
+
+func (encoder *dereferenceEncoder) Encode(ptr unsafe.Pointer, stream *Stream) {
+	if *((*unsafe.Pointer)(ptr)) == nil {
+		stream.WriteNil()
+	} else {
+		encoder.ValueEncoder.Encode(*((*unsafe.Pointer)(ptr)), stream)
+	}
+}
+
+func (encoder *dereferenceEncoder) IsEmpty(ptr unsafe.Pointer) bool {
+	dePtr := *((*unsafe.Pointer)(ptr))
+	if dePtr == nil {
+		return true
+	}
+	return encoder.ValueEncoder.IsEmpty(dePtr)
+}
+
+func (encoder *dereferenceEncoder) IsEmbeddedPtrNil(ptr unsafe.Pointer) bool {
+	deReferenced := *((*unsafe.Pointer)(ptr))
+	if deReferenced == nil {
+		return true
+	}
+	isEmbeddedPtrNil, converted := encoder.ValueEncoder.(IsEmbeddedPtrNil)
+	if !converted {
+		return false
+	}
+	fieldPtr := unsafe.Pointer(deReferenced)
+	return isEmbeddedPtrNil.IsEmbeddedPtrNil(fieldPtr)
+}
+
+type referenceEncoder struct {
+	encoder ValEncoder
+}
+
+func (encoder *referenceEncoder) Encode(ptr unsafe.Pointer, stream *Stream) {
+	encoder.encoder.Encode(unsafe.Pointer(&ptr), stream)
+}
+
+func (encoder *referenceEncoder) IsEmpty(ptr unsafe.Pointer) bool {
+	return encoder.encoder.IsEmpty(unsafe.Pointer(&ptr))
+}
+
+type referenceDecoder struct {
+	decoder ValDecoder
+}
+
+func (decoder *referenceDecoder) Decode(ptr unsafe.Pointer, iter *Iterator) {
+	decoder.decoder.Decode(unsafe.Pointer(&ptr), iter)
+}