Add package version to user agent

To enhance the 'User-Agent' used in the request headers, this commit
adds the module constant `RMT::Version`, which must always match the
package version specified in 'package/yast2-rmt.spec'.

Additionally, a unit test was created to ensure the versions always
match each other; if there is a version bump in packge spec file, the
RSpec tests will break if 'src/lib/rmt.rb' is not updated accordingly.

spec/rmt_spec.rb

@@ -0,0 +1,26 @@
+require 'rmt'
+
+describe RMT do
+  describe '.VERSION' do
+    subject(:version) { RMT::VERSION }
+
+    let(:package_version) do
+      filename = './package/yast2-rmt.spec'
+      version = nil
+
+      File.foreach(filename) do |line|
+        line.match(/^Version:\s+(?<version>(\d+\.?){3})$/) do |match|
+          version ||= match.named_captures['version']
+        end
+      end
+
+      raise "'#{filename}' does not include any line matching the expected package version format." if version.nil?
+
+      version
+    end
+
+    it 'returns the same version as specified in the package spec file' do
+      expect(version).to eq package_version
+    end
+  end
+end

src/lib/rmt.rb

@@ -0,0 +1,3 @@
+module RMT
+  VERSION = '1.3.5'.freeze
+end

src/lib/rmt/wizard_scc_page.rb

@@ -18,6 +18,7 @@
 
 require 'uri'
 require 'net/http'
+require 'rmt'
 require 'rmt/utils'
 require 'ui/event_dispatcher'
 
@@ -26,7 +27,7 @@ module RMT; end
 class RMT::WizardSCCPage < Yast::Client
   include ::UI::EventDispatcher
 
-  YAST_RMT_USER_AGENT = 'yast2-rmt'.freeze
+  YAST_RMT_USER_AGENT = "yast2-rmt/#{RMT::VERSION}".freeze
 
   def initialize(config)
     textdomain 'rmt'