【数字签名】第一次使用时crash修复

PDF Office/PDF Master/Class/DigtalSignature/DSignatureApperanceManager.swift

@@ -313,6 +313,9 @@ class DSignatureApperanceManager: NSObject {
     //MARK: Add
     func addDSignatureAppearanceData(watermark: DSignatureAppearanceData) -> Bool {
         if FileManager.default.fileExists(atPath: kDSignatureFolderPath) == false {
+            if FileManager.default.fileExists(atPath: ApplicationSupportDirectory) == false {
+                try?FileManager.default.createDirectory(atPath: ApplicationSupportDirectory, withIntermediateDirectories: false)
+            }
             try?FileManager.default.createDirectory(atPath: kDSignatureFolderPath, withIntermediateDirectories: false)
             if FileManager.default.fileExists(atPath: kDSignatureFolderPath) == false {
                 return false