* origin/topic/neverlord/version-header:
testing/zeek-version-link: Assume nm is there
Drop dependency for zeek_dynamic_plugin_base
Fixup ifdef check in Plugin.h
Update cmake_minimum_required() in test plugins
testing: Add zeek-version-link tests
Clean up ZEEK_CONFIG_SKIP_VERSION_H issues
cmake-format during merge
Also now uses CMake's ENABLE_EXPORTS target property for the zeek
executable to ensure symbols are visible to plugins. Prior to CMake
3.4, the policy was to export symbols by default for certain platforms,
but later versions need either the explicit target property or policy.
Most of these changes are either cmake-related or plugin-related.
Added a new test "plugins/legacy.zeek" to test that legacy Bro plugins
still work.
Also added a symlink bro-path-dev.in because some legacy Bro packages
won't install without it.
