Clean heron-ui backend (#3597)

* Clean heron-ui backend

 * replace tornado server with FastAPI+Jinja2+Uvicorn
 * factor out torado from heron.tools.common
 * add type annotations
 * expose port 8889 of Vagrant VM for heron-ui
 * pin to latest 4.x version of Tornado
 * visual changes to container pages

This should only be an internal refactor.

Async querying of the tracker was dropped, but could be reintroduced
using [aiohttp](https://docs.aiohttp.org/en/stable/) if speed becomes
an issue for requests that aggregate tracker data.

* Remove duplicate tracker process

heron/common/src/python/utils/__init__.py

@@ -15,5 +15,4 @@
 # specific language governing permissions and limitations
 # under the License.
 '''common utility modules'''
-__all__ = ['metrics', 'misc', 'topology', 'config', 'tracker_access',
-           'tuple', 'proc', 'log']
+__all__ = ['proc', 'log']

heron/instance/src/python/utils/__init__.py

@@ -15,5 +15,4 @@
 # specific language governing permissions and limitations
 # under the License.
 '''common utility modules'''
-__all__ = ['metrics', 'misc', 'topology', 'config', 'tracker_access',
-           'system_constants', 'system_config', 'tuple', 'proc', 'log']
+__all__ = ['system_constants', 'system_config', 'tuple']

heron/shell/src/python/BUILD

@@ -7,7 +7,7 @@ pex_library(
     ),
     reqs = [
         "requests==2.12.3",
-        "tornado==4.0.2",
+        "tornado==4.5.3",
     ],
     deps = [
         "//heron/common/src/python:common-py",

heron/tools/common/src/python/BUILD

@@ -2,14 +2,14 @@ package(default_visibility = ["//visibility:public"])
 
 pex_library(
     name = "tracker-py",
-    srcs = glob(["access/*.py"]),
+    srcs = glob(["clients/*.py"]),
 )
 
 pex_library(
     name = "common-py",
     srcs = glob(
         ["**/*.py"],
-        exclude = ["access"],
+        exclude = ["clients"],
         exclude_directories = 1,
     ),
     reqs = ["PyYAML==3.13"],