EmulatorPkg: Add Platform CI and configuration for Core CI

REF:https://bugzilla.tianocore.org/show_bug.cgi?id=2570

Add new Azure Pipeline definitions to build and run EmulatorPkg with:
  * Ubuntu GCC5
  * Windows VS2019
Add PyTool based build of EmulatorPkg
Add EmulatorPkg.ci.yaml for Core CI
Add ReadMe.md for details and instructions

Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Andrew Fish <afish@apple.com>
Cc: Ray Ni <ray.ni@intel.com>
Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>

Reviewed-by: Shenglei Zhang <shenglei.zhang@intel.com>
Reviewed-by: Bret Barkelew <bret.barkelew@microsoft.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Acked-by: Ray Ni <ray.ni@intel.com>

EmulatorPkg/EmulatorPkg.ci.yaml

@@ -0,0 +1,85 @@
+## @file
+# Core CI configuration for EmulatorPkg
+#
+# EmulatorPkg is part of Platform Ci for builds so this is only
+# used for code analysis.
+#
+# Copyright (c) Microsoft Corporation
+# SPDX-License-Identifier: BSD-2-Clause-Patent
+##
+{
+    ## options defined .pytool/Plugin/CompilerPlugin
+    "CompilerPlugin": {
+        "DscPath": "" # Don't support this test
+    },
+
+    ## options defined .pytool/Plugin/HostUnitTestCompilerPlugin
+    "HostUnitTestCompilerPlugin": {
+        "DscPath": "" # Don't support this test
+    },
+
+    ## options defined .pytool/Plugin/CharEncodingCheck
+    "CharEncodingCheck": {
+        "IgnoreFiles": []
+    },
+
+    ## options defined .pytool/Plugin/DependencyCheck
+    "DependencyCheck": {
+        "AcceptableDependencies": [
+            # For this platform all packages are allowed???
+            "MdePkg/MdePkg.dec",
+            "MdeModulePkg/MdeModulePkg.dec",
+            "EmulatorPkg/EmulatorPkg.dec",
+            "NetworkPkg/NetworkPkg.dec",
+            "EmbeddedPkg/EmbeddedPkg.dec", ## is this one OK??
+        ],
+        # For host based unit tests
+        "AcceptableDependencies-HOST_APPLICATION":[
+            "UnitTestFrameworkPkg/UnitTestFrameworkPkg.dec"
+        ],
+        # For UEFI shell based apps
+        "AcceptableDependencies-UEFI_APPLICATION":[],
+        "IgnoreInf": []
+    },
+
+    ## options defined .pytool/Plugin/DscCompleteCheck
+    "DscCompleteCheck": {
+        "IgnoreInf": [""],
+        "DscPath": ""  # Don't support this test
+    },
+
+    ## options defined .pytool/Plugin/HostUnitTestDscCompleteCheck
+    "HostUnitTestDscCompleteCheck": {
+        "IgnoreInf": [""],
+        "DscPath": "" # Don't support this test
+    },
+
+    ## options defined .pytool/Plugin/GuidCheck
+    "GuidCheck": {
+        "IgnoreGuidName": [],
+        "IgnoreGuidValue": [],
+        "IgnoreFoldersAndFiles": [],
+        "IgnoreDuplicates": [],
+    },
+
+    ## options defined .pytool/Plugin/LibraryClassCheck
+    "LibraryClassCheck": {
+        "IgnoreHeaderFile": []
+    },
+
+    ## options defined .pytool/Plugin/SpellCheck
+    "SpellCheck": {
+        "AuditOnly": True,           # Fails right now with over 270 errors
+        "IgnoreFiles": [],           # use gitignore syntax to ignore errors in matching files
+        "ExtendWords": [
+            "setjump",
+            "plong",
+            "lparam",
+            "lpdword",
+            "lpthread",
+            "lresult",
+        ],           # words to extend to the dictionary for this package
+        "IgnoreStandardPaths": [],   # Standard Plugin defined paths that should be ignore
+        "AdditionalIncludePaths": [] # Additional paths to spell check (wildcards supported)
+    }
+}