Add a patch for p7zip to address build problems triggered by p7zip Stdafx.h defining WIN64 on non-Windows x86_64 systems. Modify compileX11.sh to

check for lib7zip folder and try to apply the patch before build. Update documentation in README_7zip.txt.

compileX11.sh

@@ -1,5 +1,14 @@
 #! /bin/bash
 
+cd ./compressed_archive
+if [ ! -d "libp7zip" ]; then
+echo "You need p7zip source code to compile YACReader. \
+Please check the compressed_archive folder for further instructions."
+exit
+fi
+patch -p0 -i libp7zip.patch
+cd ..
+
 echo "Compiling YACReader"
 cd ./YACReader
 qmake "CONFIG+=release"

compressed_archive/README_7zip.txt

@@ -1,5 +1,7 @@
 If you are trying to compile YACReader, you need to donwload de source code of 7zip (Windows) or p7zip (Linux/MacOSX).
 
-Please, extract it and rename the folder to lib7zip (Windows) or libp7zip (Linux/MacOSX), then copy it to $YACREADER_SRC/compressed_archive/ (this folder)
+Please, extract it and rename the folder to lib7zip (Windows) or libp7zip (Linux/MacOSX), then copy it to $YACREADER_SRC/compressed_archive/ (this 
+folder). If you are using a 64 bit Linux-System, please apply libp7zip.patch for successfull compilation or use compileX11.sh.
+
+YACReader is compiled using 7zip/p7zip 9.20.1
 
-YACReader is compiled using 7zip/p7zip 9.20.

compressed_archive/libp7zip.patch

@@ -0,0 +1,11 @@
+--- libp7zip/CPP/myWindows/StdAfx.h	2014-06-06 23:52:13.397311952 +0200
++++ libp7zip/CPP/myWindows/StdAfx.h	2014-06-06 23:53:20.353981756 +0200
+@@ -114,7 +114,7 @@
+ 
+ #if defined( __x86_64__ )
+ 
+-#define _WIN64 1
++//#define _WIN64 1
+ 
+ #endif
+