initial steps for including symbols

@ahelwer - seems several steps are involved for enableing snupkg. I will try to see if I can get there. The NugetCommand@2 specifies whether to include symbols, but I haven't found the portion where it allows the user to specify the name of the package (to snukpg instead of nupkg).

scripts/mk_nuget_task.py

@@ -57,10 +57,13 @@ def unpack(packages):
             zip_ref = zipfile.ZipFile(path, 'r')
             zip_ref.extract("%s/bin/libz3.%s" % (package_dir, ext), "tmp")
             mk_dir("out/runtimes/%s/native" % dst)
-            shutil.move("tmp/%s/bin/libz3.%s" % (package_dir, ext), "out/runtimes/%s/native/." % dst)
+            shutil.move("tmp/%s/bin/libz3.%s" % (package_dir, ext), "out/runtimes/%s/native/." % dst)            
             if "x64-win" in f:
+                zip_ref.extract("%s/bin/libz3.%s" % (package_dir, "pdb"), "tmp")
+                mk_dir("out/runtimes/%s/native" % dst)
+                shutil.move("tmp/%s/bin/libz3.%s" % (package_dir, "pdb"), "out/runtimes/%s/native/." % dst)            
                 mk_dir("out/lib/netstandard1.4/")
-                for b in ["Microsoft.Z3.dll"]:
+                for b in ["Microsoft.Z3.dll", "Microsoft.Z3.pdb"]:
                     zip_ref.extract("%s/bin/%s" % (package_dir, b), "tmp")
                     shutil.move("tmp/%s/bin/%s" % (package_dir, b), "out/lib/netstandard1.4/%s" % b)
 

scripts/nightly.yaml

@@ -1,12 +1,12 @@
 variables:
-  z3Version: '4.8.7'
+  z3Version: '4.9.10'
 
 jobs:
 
 - job: Mac
   displayName: "Mac Build"
   pool:
-    vmImage: "macOS-10.14"
+    vmImage: "macOS-latest"
   steps:
   - script: python scripts/mk_unix_dist.py --dotnet-key=$(Build.SourcesDirectory)/resources/z3.snk
   - script: git clone https://github.com/z3prover/z3test z3test
@@ -20,7 +20,7 @@ jobs:
 - job: Ubuntu
   displayName: "Ubuntu build"
   pool:
-    vmImage: "ubuntu-16.04"
+    vmImage: "ubuntu-latest"
   steps:
   - script: python scripts/mk_unix_dist.py --dotnet-key=$(Build.SourcesDirectory)/resources/z3.snk
   - script: git clone https://github.com/z3prover/z3test z3test
@@ -148,7 +148,7 @@ jobs:
   - Windows64
   - Mac
   pool:
-    vmImage: "ubuntu-16.04"
+    vmImage: "ubuntu-latest"
   steps:
   - task: DownloadPipelineArtifact@0
     inputs: