Feature/87 add additional svc tracker bundle context funtions

[pnoltes]

This pull request introduces several new bundle context C functions and C++ ServiceTracker methods. These additions allow tracked services to be called using callbacks on the current thread through a service tracker or service tracker ID. This method of calling services is expected to be more performant than the useService(s) functions/methods, which invoke callbacks on the event thread.

For C, the following functions where added:

• celix_bundleContext_useTrackedService
• celix_bundleContext_useTrackedServices
• celix_bundleContext_useTrackedServiceWithOptions
• celix_bundleContext_useTrackedServicesWithOptions
• celix_bundleContext_getTrackedServiceCount
• celix_bundleContext_getTrackedServiceName
• celix_bundleContext_getTrackedServiceFilter

The signature of the following C function has been changed:

• celix_bundleContext_trackServices. The trackServices function signature is simplified to that it is easier to use when combined with the useTrackerService(s) calls.

For C++, the following methods were added:

• celix::ServiceTracker<I>::useService<F>
• celix::ServiceTracker<I>::useServices<F>

This pull request also prepares the removal of celix_service_tracker.h as public api. This change should make it easier to refactor the celix_service_tracker.h and implementation for a better code coverage and error handling.

Also replaces the usage of hash_map_t in the C bundle context to celix_long_hash_map_t.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 88.98072% with 40 lines in your changes are missing coverage. Please review.

Project coverage is 89.65%. Comparing base (423abb8) to head (8ca876d). Report is 13 commits behind head on master.

Files	Patch %	Lines
libs/framework/src/service_tracker.c	78.94%	24 Missing :warning:
libs/framework/src/bundle_context.c	92.63%	14 Missing :warning:
libs/framework/include/celix/Trackers.h	96.77%	1 Missing :warning:
libs/framework/src/bundle.c	92.85%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #729 +/- ## ========================================== + Coverage 89.32% 89.65% +0.32% ========================================== Files 216 216 Lines 25153 25652 +499 ========================================== + Hits 22468 22998 +530 + Misses 2685 2654 -31 ```

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[pnoltes]

Currently it is not possible to call celix_bundleContext_trackServices* functions with a "use tracker service" callback (because a write lock is needed while holding a read lock). I think this can be enabled using a atomic use count, but I will do that in a separate PR.

For now I will merge this PR.