added user independent sections and started db migration work

pkg/core/permission.go

@@ -7,7 +7,6 @@ type Permission int
 const (
 	Invalid Permission = iota
 	Public
-	Internal
 	Private
 )
 
@@ -16,37 +15,27 @@ func ParsePermString(p string) Permission {
 	case "1":
 		return Public
 	case "2":
-		return Internal
-	case "3":
 		return Private
 	}
 	return Invalid
 }
 
-func ReadPerm(username string, p *Page) bool {
-	switch p.Perm {
+func ReadPerm(username string, p Permission, s Section) bool {
+	switch p {
 	case Public:
 		return true
-	case Internal:
-		return username != ""
 	case Private:
-		return username == p.Owner
+		_, c := Contains(username, s.Members)
+		return c
 	}
 	return false
 }
 
-func WritePerm(username, section string, p *Page) bool {
-	if section != WikiSection && section != username {
-		return false
-	}
-	switch p.Perm {
-	case Public, Internal:
-		if p.Owner == WikiSection {
-			return username != ""
-		}
-		return username == p.Owner
-	case Private:
-		return username == p.Owner
+func WritePerm(username string, p Permission, s Section) bool {
+	switch p {
+	case Public, Private:
+		_, c := Contains(username, s.Members)
+		return c
 	}
 	return false
 }