[MTOOLCHAINS-29] added optional <fail> parameter

[hsynkrtl]

possibility not to fail if toolchain.xml is not available

[rfscholte]

The issue already said we're not going to fix this, you should consider profiles instead. So I'll close this PR

[hsynkrtl]

The decision not to fix was a false decision in the first place.

The changes of jdk9+ made the toolchain essencial again, But i am sure mostly, a warning would be enough. At the first place the toolchains-plugin should provide the ability to share configuration, not to enforce. This job does the enforcer plugin quite well with a great set of built-in rules.

I could imagine that it is maybe posible to switch jdk just by using profiles, even without toolchain. But that would just blow up the POM. And it is the same with your consideration to enable or disable toolchain by profiles.

Just because there is a workaround, This feature shouldn't rejected.

Despite of the last release, the toolchain plugin just didn't developed for a long time. This would be a nice movement to get more similarity to enforcer plugin.

This is an optional convenient and common (enforcer-plugin) feature. So come on.

[jira-importer]

Resolve #123