An Execute shell build step with simple command `env` shows that none of the *_URL environment variables are being imported to the shell.

Scripts that access the Jenkins REST API rely on these vars to execute.

E.g. output of `env` step on 1.495

BUILD_CAUSE_USERIDCAUSE=true
HUDSON_SERVER_COOKIE=62a4ddfd88c783b78b6ae030cb9d0617
SHELL=/bin/bash
TMPDIR=/var/folders/zv/6gwf54fj3c791gjxcddqp9t400007c/T/
BUILD_TAG=jenkins-ios-app_master-17
WORKSPACE=/Users/Shared/Jenkins/Home/jobs/ios-app_master/workspace
com.apple.java.jvmTask=CommandLine.java.java.java.java.java.java
USER=jenkins
__CF_USER_TEXT_ENCODING=0xEC:0:0
GIT_COMMIT=925e5ce56d7b6f0b67015131f8dd9d85e9c1168b
JENKINS_HOME=/Users/Shared/Jenkins/Home
PATH=/usr/bin:/bin:/usr/sbin:/sbin
PWD=/Users/Shared/Jenkins/Home/jobs/ios-app_master/workspace
JOB_NAME=ios-app_master
JAVA_MAIN_CLASS_8793=Main
com.apple.java.jvmMode=client
BUILD_CAUSE=USERIDCAUSE
BUILD_ID=2012-12-29_10-31-47
HOME=/Users/Shared/Jenkins
SHLVL=1
GIT_BRANCH=origin/master
JENKINS_SERVER_COOKIE=62a4ddfd88c783b78b6ae030cb9d0617
EXECUTOR_NUMBER=0
NODE_LABELS=master
LOGNAME=jenkins
HUDSON_HOME=/Users/Shared/Jenkins/Home
NODE_NAME=master
BUILD_NUMBER=17
HUDSON_COOKIE=fadc3c90-aca8-4b58-8850-5aded45d1348
JAVA_ARCH=x86_64
SECURITYSESSIONID=186d2
_=/usr/bin/env