Add: Unittests (coscine/issues#1203)

...ools/linq2db.t4models/FirebirdSql.Data.FirebirdClient.dll

src/.tools/linq2db.t4models/Init.ps1

src/.tools/linq2db.t4models/Microsoft.SqlServer.Types.dll

src/.tools/linq2db.t4models/MySql.Data.dll

src/.tools/linq2db.t4models/Npgsql.dll

src/.tools/linq2db.t4models/Oracle.ManagedDataAccess.dll

src/.tools/linq2db.t4models/SQLite.Interop.dll

src/.tools/linq2db.t4models/System.Data.SQLite.dll

...ls/linq2db.t4models/System.Threading.Tasks.Extensions.dll

src/.tools/linq2db.t4models/linq2db.dll

src/Pid.Tests/App.config

src/Pid.Tests/DefaultControllerTests.cs

src/Pid.Tests/NLog.config

src/Pid.Tests/NLog.xsd

src/Pid.Tests/Pid.Tests.csproj

src/Pid.Tests/PidControllerTests.cs

src/Pid.Tests/Properties/AssemblyInfo.cs

src/Pid.Tests/packages.config

src/Pid.sln

src/Pid/App.config