[platform-dev] [api-tools] Support for package-export checks

[Christoph Läubrich <laeubi@xxxxxxxxxxxxxx>]

Hello everyone,

with [1] we now have a very first step to package export validation in 
PDE api-tools.

Due to the nature of how API tools currently work we will not see any 
issues in the verification builds yet but maybe some new errors in the 
workspace when the new I-Build is there and you update your eclipse-sdk 
because we never checked these before.

After the new ibuild is available I plan to enable the use of snapshot 
api tools for this release so we can see such issues in the verification 
builds as well.

If you see any false positives, or think that a reported suggestion 
might be wrong, please report the case here [2] so we can fix the case, 
in all other cases we should fix the reported issue.

[1] https://github.com/eclipse-pde/eclipse.pde/pull/1558
[2] https://github.com/eclipse-pde/eclipse.pde/issues