added JCloudsPropertiesFromEnv + Test; updated the properties management for jclouds location
renamed JcloudsPropertiesFromEnv to JcloudsPropertiesFromBrooklynProperties
Remove JcloudsLocationFactory; add location-metadata.properties

- Instead of hardcoding metadata (e.g. lat/lon coordinates) in
  the JcloudsLocationFactory class, the BrooklynProperties looks up
  the location-metadata.properties file.
- Look up properties with prefix brooklyn.jclouds.<PROVIDER>:<REGION>.*
- Deleted deprecated (unused) CommandLineLocations
Add ISO_3166 config key
Jclouds properties: remove sanitize()
Deleted CredentialsFromEnv

- And converted JcloudsLocationRebindTest from groovy to java
JcloudsResolver: accept locationFlags as-is (without needing prefix)
Add missing location-metadata.properties

- values extracted from the (deleted) JcloudsLocationFactory
jclouds-properties cleanup: incorporate review comments
Merge pull request #791 from aledsage/feature/credentialFromEnv

add JCloudsPropertiesFromEnv