2-add-keyword-support (#6)

More development.

More types.
Fixed attribute groups in requests.
Started on client.
Saving data to file.

More types. Printing from chromeos works a little bit.

More types.

Spelling corrections.

WIP: Fix keyword handling

Move request to a separate file and add test.

Co-authored-by: Henrik Sölver <henrik.solver@gmail.com>
Reviewed-on: #6
Co-Authored-By: henrik <henrik.solver@gmail.com>
Co-Committed-By: henrik <henrik.solver@gmail.com>

packages/ipp/mimemediatype.go

@@ -0,0 +1,32 @@
+package ipp
+
+type mimeMediaType struct {
+	sos *setOfStrings
+}
+
+func NewMimeMediaType(name string, values ...string) *mimeMediaType {
+
+	m := new(mimeMediaType)
+	m.sos = NewSetOfStrings(name, mimeMediaTypeValueTag, values)
+	return m
+}
+
+func (m mimeMediaType) String() string {
+	return m.sos.String()
+}
+
+func (m *mimeMediaType) size() int {
+	return m.sos.size()
+}
+
+func (m *mimeMediaType) valueTag() tag {
+	return m.sos.valueTag()
+}
+
+func (m *mimeMediaType) marshal() []byte {
+	return m.sos.marshal()
+}
+
+func (m *mimeMediaType) addValue(v string) {
+	m.sos.AddValue(v)
+}