[VOL-5031] - Pre-release voltha-onos build

[VOL-5099] - verify_foltha-onos-sanity-test FAIL

app-install.sh
tests/version-check.sh
----------------------
  o shellcheck cleanups
  o Improve error detection and reporting.
  o cd '..' early VS resolving relative paths everywhere.
  o Replace $(basename) with shell string builtins.
  o use local vars to shorten paths and avoid extra string concatenation.
  o Added error detection in "<app name=" gathering, shell commands can
    fail allowing manipulation in APP_INSTALL_ROOT VS A_I_R/$name.

Makefile
makefiles/virtualenv.mk
-----------------------
  o Update requirements.txt read check to not require existence
    of an empty *.txt file on disk.

dependencies.xml
----------------
  o Update component dependencies to match the latest deployed versions.
  o https://wiki.opennetworking.org/display/VOLTHA/v2.12+Deployments
  o Still pending: segmentrouting.version and kafka.

Change-Id: I05d2d71521fa56ea788cc959e1ce88b1d38e1b2b
diff --git a/VERSION b/VERSION
index d4bda08..fc3aa77 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-5.1.8
+5.1.9