ZODB Components: Do not export some Workflow History fields.

These are completely useless and create conflicts with VCSs.
ZODB Components: Disable spurious Pylint warning: 'Access to a protected member %s of a client class'.
ZODB Components: When checking source, improve message when a SyntaxError is raised through compile().
ZODB Components: Do not catch BaseException (bad practise).
ZODB Components: Like Python Script, use Ace Editor annotations to check source code without saving.

Also, switch to Pylint for Python Script source code checking to use the same
code for both.
Cosmetic: Fix Pylint warnings.