Add [ForceUnionAttribute] to allow forced type serialization

[Jannify]

Closes: #7

[Measurity]

Benchmark run:

|           Method |     Job |              Runtime |      Categories |        Mean |    Error |   StdDev | Ratio | RatioSD |    Gen0 |    Gen1 |    Gen2 | Allocated | Alloc Ratio |
|----------------- |-------- |--------------------- |---------------- |------------:|---------:|---------:|------:|--------:|--------:|--------:|--------:|----------:|------------:|
|   NewtonsoftJson | NET_472 | .NET Framework 4.7.2 | Deserialization |   503.14 us | 1.536 us | 1.362 us |  1.00 |    0.00 | 27.3438 |  6.8359 |       - | 172.19 KB |        1.00 |
|      NetCoreJson | NET_472 | .NET Framework 4.7.2 | Deserialization |   705.07 us | 2.721 us | 2.545 us |  1.40 |    0.01 | 16.6016 |  3.9063 |       - | 106.12 KB |        0.62 |
|    XmlSerializer | NET_472 | .NET Framework 4.7.2 | Deserialization |   532.08 us | 2.446 us | 2.288 us |  1.06 |    0.00 | 29.2969 |  6.8359 |       - | 183.02 KB |        1.06 |
| DataContractJson | NET_472 | .NET Framework 4.7.2 | Deserialization | 1,879.06 us | 4.792 us | 4.248 us |  3.73 |    0.01 | 89.8438 | 21.4844 |       - | 562.47 KB |        3.27 |
|         Utf8Json | NET_472 | .NET Framework 4.7.2 | Deserialization |   278.43 us | 1.311 us | 1.226 us |  0.55 |    0.00 | 41.5039 | 41.5039 | 41.5039 | 239.03 KB |        1.39 |
|      MessagePack | NET_472 | .NET Framework 4.7.2 | Deserialization |   184.34 us | 0.818 us | 0.765 us |  0.37 |    0.00 | 17.0898 |  3.9063 |       - | 106.43 KB |        0.62 |
|                  |         |                      |                 |             |          |          |       |         |         |         |         |           |             |
|   NewtonsoftJson |   NET_7 |             .NET 7.0 | Deserialization |   407.98 us | 1.399 us | 1.308 us |  1.00 |    0.00 |  9.2773 |  1.9531 |       - | 156.87 KB |        1.00 |
|      NetCoreJson |   NET_7 |             .NET 7.0 | Deserialization |   340.38 us | 1.773 us | 1.659 us |  0.83 |    0.01 |  6.3477 |  0.9766 |       - | 111.57 KB |        0.71 |
|    XmlSerializer |   NET_7 |             .NET 7.0 | Deserialization |   414.89 us | 1.987 us | 1.859 us |  1.02 |    0.01 | 11.7188 |  2.9297 |       - | 195.49 KB |        1.25 |
| DataContractJson |   NET_7 |             .NET 7.0 | Deserialization | 1,456.69 us | 5.560 us | 5.200 us |  3.57 |    0.02 | 33.2031 |  7.8125 |       - | 553.67 KB |        3.53 |
|         Utf8Json |   NET_7 |             .NET 7.0 | Deserialization |   242.99 us | 1.437 us | 1.344 us |  0.60 |    0.00 | 41.5039 | 41.5039 | 41.5039 | 239.84 KB |        1.53 |
|      MessagePack |   NET_7 |             .NET 7.0 | Deserialization |    64.68 us | 0.461 us | 0.432 us |  0.16 |    0.00 |  6.5918 |  1.4648 |       - | 108.16 KB |        0.69 |
|                  |         |                      |                 |             |          |          |       |         |         |         |         |           |             |
|   NewtonsoftJson | NET_472 | .NET Framework 4.7.2 |   Serialization |   452.81 us | 1.128 us | 1.000 us |  1.00 |    0.00 | 41.5039 | 41.5039 | 41.5039 | 294.21 KB |        1.00 |
|      NetCoreJson | NET_472 | .NET Framework 4.7.2 |   Serialization |   502.96 us | 1.469 us | 1.374 us |  1.11 |    0.00 | 64.4531 | 64.4531 | 64.4531 | 315.83 KB |        1.07 |
|    XmlSerializer | NET_472 | .NET Framework 4.7.2 |   Serialization |   610.26 us | 2.341 us | 2.190 us |  1.35 |    0.01 | 82.0313 | 41.0156 | 41.0156 | 507.09 KB |        1.72 |
| DataContractJson | NET_472 | .NET Framework 4.7.2 |   Serialization |   625.97 us | 1.958 us | 1.831 us |  1.38 |    0.01 | 35.1563 | 35.1563 | 35.1563 | 232.08 KB |        0.79 |
|         Utf8Json | NET_472 | .NET Framework 4.7.2 |   Serialization |   268.17 us | 1.850 us | 1.730 us |  0.59 |    0.00 | 41.5039 | 41.5039 | 41.5039 | 199.48 KB |        0.68 |
|      MessagePack | NET_472 | .NET Framework 4.7.2 |   Serialization |    73.82 us | 0.374 us | 0.350 us |  0.16 |    0.00 | 17.8223 |  2.9297 |       - | 109.98 KB |        0.37 |
|                  |         |                      |                 |             |          |          |       |         |         |         |         |           |             |
|   NewtonsoftJson |   NET_7 |             .NET 7.0 |   Serialization |   224.71 us | 1.285 us | 1.202 us |  1.00 |    0.00 |  9.7656 |  1.9531 |       - | 163.78 KB |        1.00 |
|      NetCoreJson |   NET_7 |             .NET 7.0 |   Serialization |   269.30 us | 1.289 us | 1.206 us |  1.20 |    0.01 | 39.5508 | 39.5508 | 39.5508 |  315.5 KB |        1.93 |
|    XmlSerializer |   NET_7 |             .NET 7.0 |   Serialization |   390.39 us | 0.700 us | 0.621 us |  1.74 |    0.01 | 90.8203 | 90.8203 | 90.8203 | 420.04 KB |        2.56 |
| DataContractJson |   NET_7 |             .NET 7.0 |   Serialization |   482.34 us | 1.305 us | 1.157 us |  2.15 |    0.02 | 35.6445 | 35.6445 | 35.6445 | 227.69 KB |        1.39 |
|         Utf8Json |   NET_7 |             .NET 7.0 |   Serialization |   231.57 us | 1.436 us | 1.343 us |  1.03 |    0.01 | 41.5039 | 41.5039 | 41.5039 | 194.08 KB |        1.19 |
|      MessagePack |   NET_7 |             .NET 7.0 |   Serialization |    37.07 us | 0.162 us | 0.152 us |  0.16 |    0.00 |  6.7139 |  0.8545 |       - | 110.47 KB |        0.67 |

[tornac1234]

Could you add some graph for this benchmark please ?