Support encrypted backup files

Also includes features merged from:

Update twrpTar by kokotas

Revised function entryExists().
Added function to get archive's uncompressed size.
Added option to exclude item(s) from the archive.
Revised forks()

Change-Id: I01fa2c81643161984eff2625247af75990684bd9
diff --git a/partitions.hpp b/partitions.hpp
index 704ba68..3ed4da6 100644
--- a/partitions.hpp
+++ b/partitions.hpp
@@ -110,6 +110,8 @@
 	string Storage_Name;                                                      // Name displayed in the partition list for storage selection
 	string Backup_FileName;                                                   // Actual backup filename
 	Backup_Method_enum Backup_Method;                                         // Method used for backup
+	bool Can_Encrypt_Backup;                                                  // Indicates if this item can be encrypted during backup
+	bool Use_Userdata_Encryption;                                             // Indicates if we will use userdata encryption splitting on an encrypted backup
 	bool Has_Data_Media;                                                      // Indicates presence of /data/media, may affect wiping and backup methods
 	bool Has_Android_Secure;                                                  // Indicates the presence of .android_secure on this partition
 	bool Is_Storage;                                                          // Indicates if this partition is used for storage for backup, restore, and installing zips