Add @Inherited to annotations targeting ElementType.TYPE

[beatngu13]

See this comment:

As pointed out by @Michael1993 in #449, there are more annotations – besides the environment variable and system property extensions – we should consider making @Inherited.

I believe this only makes sense for annotations targeting ElementType.TYPE, since we are dealing with test base classes. Searching for ElementType.TYPE yields:

* `@DefaultLocale`

* `@DefaultTimeZone`

* `@Issue`

* `@Stopwatch`

Plus all the @Reads*/@Writes* annotations.

So, I tend to reopen this issue until we make the above @Inherited, too. What do you guys think?

As suggested by @nipafx, "one PR per extension" is preferred.

Example PR/changes for entry-based annotations (i.e. environment variable and system property extensions): #449

[beatngu13]

Side note: In contrast to #448, I labeled this issue as "enhancement" rather than "bug". IMHO the annotations/extensions basically work as expected, adding @Inherited is new functionality. However, in case somebody disagrees, feel free to adjust the corresponding label.

[Bukama]

I also see this as new functionality. We need to keep in mind that nothing gets broken, esp. @Issue should be carefully watched as the search for the annotation not only happens in one place.