Stopping check on first error

It is possible to check everything by passing command line option, but not
enabled by default to save some time in initial check.

btw. I really miss goto, would make code so much cleaner...
Use latbuild for staging results check
Allow staging with different parent

Allow creation of staging project with completely arbitrary project as a parent
project.
Allow creation of staging projects without sr#

Up to now sr# was required to create a staging project, now target project name
can be used (including package) to create a new staging project.
Merge pull request #51 from miska/master

Few improvements for staging plugin