Fixed ext signature and mounting

src/binwalk/config/extract.conf

@@ -67,7 +67,7 @@
 # Try mounting the file system (this requires root privileges)
 ^squashfs filesystem:squashfs:mkdir squashfs-root && mount -t squashfs '%e' squashfs-root:0:False
 ^cramfs filesystem:cramfs:mkdir cramfs-root && mount -t cramfs '%e' cramfs-root:0:False
-^ext2 filesystem:ext2:mkdir ext2-root && mount -t ext2 '%e' ext2-root:0:False
+^linux ext filesystem:ext2:mkdir ext-root && mount '%e' ext-root:0:False
 ^romfs filesystem:romfs:mkdir romfs-root && mount -t romfs '%e' romfs-root:0:False
 
 # Use sviehb's jefferson.py tool for JFFS2 extraction

src/binwalk/magic/filesystems

@@ -501,7 +501,7 @@
 >0x43A      leshort         <0              {invalid}invalid state
 >0x43C      leshort         >3              {invalid}invalid error behavior
 >0x43C      leshort         <0              {invalid}invalid error behavior
->0x43C      lelong          >1              {invalid}invalid major revision
+>0x43C      lelong          >4              {invalid}invalid major revision
 >0x43C      lelong          <0              {invalid}invalid major revision
 >0x43C      lelong          x               rev %d
 >0x43E      leshort         x               \b.%d,