URLs in project readme are wrong

[paulc4]

The following links in https://github.com/spring-projects/spring-insight-plugins/blob/master/README.textile are broken:

1. See more at http://www.springsource.org/insight
   This is an obsolete URL and results in a Spring Boot "Whitelabel Error Page" 404
2. Download Insight Developer Edition from <here> references
   http://devedition-downloader.cloudfoundry.com/download/maven.springframework.org/snapshot/1.9.3-CI-SNAPSHOT
   This does not exist.