Refactor install_python function

It was extract the installation of pip packages from the
install_python function, this change allows to install python
packages isolated. This also includes the manual configuration
of java certificates required for maven execution.

Change-Id: Iac60d7521101d5c4997f95c16f4decd857cc5c3c
Signed-off-by: Victor Morales <victor.morales@intel.com>
diff --git a/bootstrap/vagrant-onap/lib/functions b/bootstrap/vagrant-onap/lib/functions
index b0c6e97..a2bb98e 100755
--- a/bootstrap/vagrant-onap/lib/functions
+++ b/bootstrap/vagrant-onap/lib/functions
@@ -62,6 +62,8 @@
 function install_dev_tools {
     install_package apt-transport-https
     install_package ca-certificates
+    # ca-certificates-java is not a dependency in the Oracle JDK/JRE so this must be explicitly installed.
+    /var/lib/dpkg/info/ca-certificates-java.postinst configure
     install_package curl
 }
 
@@ -122,11 +124,23 @@
 function install_python {
     install_package python2.7
     install_package python-dev
-    curl -sL https://bootstrap.pypa.io/get-pip.py | python
-    pip install tox
 }
 
-# install_docker() - Download and install docker-engine 
+# _install_pip() - Install Python Package Manager
+function _install_pip {
+    install_python
+    curl -sL https://bootstrap.pypa.io/get-pip.py | python
+}
+
+# install_python_package() - Install a python module
+function install_python_package {
+    local python_package=$1
+
+    _install_pip
+    pip install $python_package
+}
+
+# install_docker() - Download and install docker-engine
 function install_docker {
     if is_package_installed docker-ce; then
         return
@@ -192,7 +206,7 @@
     pushd $src_folder
     if [ -f pom.xml ]; then
         install_maven
-        mvn clean install -U -DskipTests=true -Dmaven.test.skip=true -Dmaven.javadoc.skip=true -Dadditionalparam=-Xdoclint:none
+        mvn clean install -DskipTests=true -Dmaven.test.skip=true -Dmaven.javadoc.skip=true -Dadditionalparam=-Xdoclint:none
     fi
     popd
 }