Export Apk.RepoURL to make it show up in the cache

Also useful to have it exported.

Bump the cache version since current caches don't have the repo url at
all.

Fixes #19 (again).

cmd/fdroidcl/update.go

@@ -143,7 +143,7 @@ func indexPath(name string) string {
 	return filepath.Join(mustData(), name+".jar")
 }
 
-const cacheVersion = 1
+const cacheVersion = 2
 
 type cache struct {
 	Version int

index.go

@@ -86,7 +86,7 @@ func (a *App) IconURLForDensity(density IconDensity) string {
 	if len(a.Apks) == 0 {
 		return ""
 	}
-	return fmt.Sprintf("%s/%s/%s", a.Apks[0].repoURL,
+	return fmt.Sprintf("%s/%s/%s", a.Apks[0].RepoURL,
 		getIconsDir(density), a.Icon)
 }
 
@@ -196,15 +196,15 @@ type Apk struct {
 	Hash    HexHash   `xml:"hash"`
 
 	AppID   string `xml:"-"`
-	repoURL string `xml:"-"`
+	RepoURL string `xml:"-"`
 }
 
 func (a *Apk) URL() string {
-	return fmt.Sprintf("%s/%s", a.repoURL, a.ApkName)
+	return fmt.Sprintf("%s/%s", a.RepoURL, a.ApkName)
 }
 
 func (a *Apk) SrcURL() string {
-	return fmt.Sprintf("%s/%s", a.repoURL, a.SrcName)
+	return fmt.Sprintf("%s/%s", a.RepoURL, a.SrcName)
 }
 
 func (a *Apk) IsCompatibleABI(ABIs []string) bool {
@@ -260,7 +260,7 @@ func LoadIndexXML(r io.Reader) (*Index, error) {
 		for j := range app.Apks {
 			apk := &app.Apks[j]
 			apk.AppID = app.ID
-			apk.repoURL = index.Repo.URL
+			apk.RepoURL = index.Repo.URL
 		}
 	}
 	return &index, nil