JCLOUDS-79: Fix cli start scripts for Windows

After adding the change about to made by https://github.com/jclouds/jclouds-cli/pull/3, works locally:
```
C:\...\jclouds-cli-1.7.0-SNAPSHOT\bin>set OPTS=-Djclouds.provider=aws-s3 -Djclouds.identity=$IDENTITY -Djclouds.credential=$CREDENTIAL

C:\...\jclouds-cli-1.7.0-SNAPSHOT\bin>jclouds.bat blobstore container-list
shell.bat: Ignoring predefined value for KARAF_HOME
log4j:WARN No appenders could be found for logger (org.jclouds.rest.internal.InvokeSyncToAsyncHttpMethod).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
Authorization error: The AWS Access Key Id you provided does not exist in our records.
```