Don't override a globally set MAVEN_OPTS, especially when there are no jenv
options. Besides, when trying to set exportedKey[MAVEN_OPTS] as MAVEN_OPTS
is already set, MAVEN_OPTS as the key is expanded, resulting in an error
message:
-Xmx1g -XX:MaxPermSize=256m: syntax error in expression (error token is ":MaxPermSize=256m")
Merge branch 'master' into maven_opts
Don't override a globally set build option (for ant, gradle, maven or sbt),
especially when there are no jenv options.
Add a note about the build tools wrappers in "Getting started".
Unset JENV_OPTIONS in all cases, so "jenv info" will not claim the options
will be added to the command line.
Actually, don't write the warning to stderr, it's _only_ a warning, not
an error.
Merge pull request #11 from fpavageau/maven_opts

No overriding of pre-set build tools options