Add work around to tools/download-maven.sh to modify maven/bin/mvn so that build on Solaris works also.
Can be reverted, as soon as new maven with fix for https://jira.codehaus.org/browse/MNG-5658 is available.
Merge pull request #6452 from bstansberry/pr6447

Replacement: Add work around to tools/download-maven.sh to modify maven/bin/mvn so th...