common: fix app version

Our app version wasn't correct per MS's spec.  Modify it
to match the XX.YYYY format.

common/appproperties.go

@@ -8,6 +8,8 @@
 package common
 
 import (
+	"fmt"
+	"strconv"
 	"strings"
 
 	"baliance.com/gooxml"
@@ -27,7 +29,10 @@ func NewAppProperties() AppProperties {
 	p.SetApplication("baliance.com/gooxml")
 	p.SetDocSecurity(0)
 	p.SetLinksUpToDate(false)
-	p.SetApplicationVersion(strings.Replace(gooxml.ReleaseVersion, "v", "", -1))
+	// trim the 'v'
+	ver := strings.Replace(gooxml.ReleaseVersion, "v", "", -1)
+	f, _ := strconv.ParseFloat(ver, 64)
+	p.SetApplicationVersion(fmt.Sprintf("%07.4f", f))
 	return p
 }
 
@@ -64,7 +69,8 @@ func (a AppProperties) ApplicationVersion() string {
 	return ""
 }
 
-// SetApplicationVersion sets the version of the application that created the document.
+// SetApplicationVersion sets the version of the application that created the
+// document.  Per MS, the verison string mut be in the form 'XX.YYYY'.
 func (a AppProperties) SetApplicationVersion(s string) {
 	a.x.AppVersion = &s
 }

common/appproperties_test.go

@@ -8,6 +8,8 @@
 package common_test
 
 import (
+	"fmt"
+	"strconv"
 	"strings"
 	"testing"
 
@@ -30,7 +32,8 @@ func TestNewAppDefaultProperties(t *testing.T) {
 		t.Errorf("unexpected application: %s", got)
 	}
 
-	if got := ap.ApplicationVersion(); got != strings.Replace(gooxml.ReleaseVersion, "v", "", -1) {
+	fv, _ := strconv.ParseFloat(strings.Replace(gooxml.ReleaseVersion, "v", "", -1), 64)
+	if got := ap.ApplicationVersion(); got != fmt.Sprintf("%07.4f", fv) {
 		t.Errorf("unexpected application version: %s", got)
 	}
 	ap.X().AppVersion = nil

version.go

@@ -9,8 +9,9 @@ package gooxml
 
 import "time"
 
-// Release is the last release version of the software.
-var ReleaseVersion = "v0.4.0"
+// ReleaseVersion is the last release version of the software and must be in the
+// format x.y
+var ReleaseVersion = "v0.5000"
 
 // ReleaseDate is the release date of the source code for licensing purposes.
 var ReleaseDate = time.Date(2018, 1, 4, 0, 0, 0, 0, time.UTC)