Fixed a bunch of issues

- App now functions again via Newtonsoft.Json and refactored EF Core queries.
- Added missing migrations for BackEnd.
- Fixed a bunch of issues with Home and My Agenda page rendering, including #100, and made setting of page title's consistent.
- Deleted unused pages.

Author: DamianEdwards

Directory.Build.props

@@ -7,5 +7,6 @@
       https://dotnetfeed.blob.core.windows.net/dotnet-core-preview7-012802/index.json;
       https://grpc.jfrog.io/grpc/api/nuget/v3/grpc-nuget-dev;
     </RestoreSources>
+    <DisableImplicitAspNetCoreAnalyzers>true</DisableImplicitAspNetCoreAnalyzers>
   </PropertyGroup>
 </Project>

src/BackEnd/Controllers/AttendeesController.cs

@@ -45,9 +45,11 @@ public async Task<ActionResult<List<SessionResponse>>> GetSessions(string userna
                                              .Include(s => s.SessionSpeakers)
                                                  .ThenInclude(ss => ss.Speaker)
                                              .Where(s => s.SessionAttendees.Any(sa => sa.Attendee.UserName == username))
-                                             .Select(m => m.MapSessionResponse())
+                                             //.Select(m => m.MapSessionResponse())
                                              .ToListAsync();
-            return sessions;
+
+            // BUG: Working around EF Core 3.0 issue: https://github.com/aspnet/EntityFrameworkCore/issues/16318
+            return sessions.Select(s => s.MapSessionResponse()).ToList();
         }
 
         [HttpPost]

src/BackEnd/Controllers/SessionsController.cs

@@ -27,10 +27,13 @@ public async Task<ActionResult<List<SessionResponse>>> Get()
             var sessions = await _db.Sessions.AsNoTracking()
                                              .Include(s => s.Track)
                                              .Include(s => s.SessionSpeakers)
-                                                .ThenInclude(ss => ss.Speaker)
-                                             .Select(m => m.MapSessionResponse())
+                                             .ThenInclude(ss => ss.Speaker)
+                                             //.Select(m => m.MapSessionResponse())
                                              .ToListAsync();
-            return sessions;
+
+            // BUG: Working around EF Core 3.0 issue: https://github.com/aspnet/EntityFrameworkCore/issues/16318
+            return sessions.Select(s => s.MapSessionResponse())
+                           .ToList();
         }
 
         [HttpGet("{id}")]

src/BackEnd/Controllers/SpeakersController.cs

@@ -25,10 +25,11 @@ public async Task<ActionResult<List<SpeakerResponse>>> GetSpeakers()
             var speakers = await _db.Speakers.AsNoTracking()
                                              .Include(s => s.SessionSpeakers)
                                                 .ThenInclude(ss => ss.Session)
-                                             .Select(s => s.MapSpeakerResponse())
+                                             //.Select(s => s.MapSpeakerResponse())
                                              .ToListAsync();
 
-            return speakers;
+            // BUG: Working around EF Core 3.0 issue: https://github.com/aspnet/EntityFrameworkCore/issues/16318
+            return speakers.Select(s => s.MapSpeakerResponse()).ToList();
         }
 
         [HttpGet("{id}")]