libguestfs security and bug fix update

1:1.20.11-20 - inspection: fix detection of /usr in separate partition resolves: rhbz1388407 1:1.20.11-19 - libguestfs-java: bump the java Require to = 1.7.0, matching the Build-Require, and the generated bytecode resolves: rhbz1319086 1:1.20.11-18 - Fix buffer overflow and information leak...