Make util a namespace

Fixes #1581

This basically renames the __init__.py file in opentelemetry-api/util to
make opentelemetry.util a proper namespace. This is needed since we are
now adding components in the contrib repo in this namespace. More
information here:

https://packaging.python.org/guides/packaging-namespace-packages/#native-namespace-packages

Author: ocelotl

Diff for: .github/workflows/test.yml

@@ -10,7 +10,7 @@ env:
   # Otherwise, set variable to the commit of your branch on
   # opentelemetry-python-contrib which is compatible with these Core repo
   # changes.
-  CONTRIB_REPO_SHA: 263adc5f7f524fae2c84571f656cef0896de0868
+  CONTRIB_REPO_SHA: 74af6ab48505cdb148de46fb12cf0802a199f297
 
 jobs:
   build:

Diff for: opentelemetry-api/src/opentelemetry/trace/__init__.py

@@ -101,7 +101,8 @@
     format_trace_id,
 )
 from opentelemetry.trace.status import Status
-from opentelemetry.util import _load_trace_provider, types
+from opentelemetry.util import types
+from opentelemetry.util.providers import _load_trace_provider
 
 logger = getLogger(__name__)
 

Diff for: opentelemetry-api/src/opentelemetry/util/__init__.py renamed to opentelemetry-api/src/opentelemetry/util/providers.py

@@ -56,7 +56,8 @@
 from opentelemetry.trace import SpanContext
 from opentelemetry.trace.propagation import SPAN_KEY
 from opentelemetry.trace.status import Status, StatusCode
-from opentelemetry.util import time_ns, types
+from opentelemetry.util import types
+from opentelemetry.util.providers import time_ns
 
 logger = logging.getLogger(__name__)
 

Diff for: opentelemetry-sdk/src/opentelemetry/sdk/trace/__init__.py

@@ -29,7 +29,7 @@
     OTEL_BSP_SCHEDULE_DELAY,
 )
 from opentelemetry.sdk.trace import ReadableSpan, Span, SpanProcessor
-from opentelemetry.util import time_ns
+from opentelemetry.util.providers import time_ns
 
 logger = logging.getLogger(__name__)
 

Diff for: opentelemetry-sdk/src/opentelemetry/sdk/trace/export/__init__.py

@@ -38,7 +38,7 @@
 from opentelemetry.sdk.util import ns_to_iso_str
 from opentelemetry.sdk.util.instrumentation import InstrumentationInfo
 from opentelemetry.trace.status import StatusCode
-from opentelemetry.util import time_ns
+from opentelemetry.util.providers import time_ns
 
 
 def new_tracer() -> trace_api.Tracer:

Diff for: opentelemetry-sdk/tests/trace/test_trace.py

@@ -16,7 +16,7 @@
 import unittest
 
 from opentelemetry.shim.opentracing_shim import util
-from opentelemetry.util import time_ns
+from opentelemetry.util.providers import time_ns
 
 
 class TestUtil(unittest.TestCase):