Optimize Create and add tests

[mitikov]

Got rid of LINQ if favor of hand-baked cycles.

[ogxd]

I just added a quick benchmark on that Create method

Before

| Method | FileName             | Mean         | Error       | StdDev      | Allocated |
|------- |--------------------- |-------------:|------------:|------------:|----------:|
| Create | census-income.zip    | 278,355.2 us | 2,380.80 us | 2,110.52 us | 273.89 MB |
| Create | census1881_srt.zip   |  27,132.1 us |   169.16 us |   141.26 us |  28.08 MB |
| Create | census1881_srt.zip   |  29,249.5 us |   376.26 us |   351.96 us |  28.08 MB |
| Create | census1881.zip       |  45,001.6 us |   469.50 us |   439.17 us |  42.22 MB |
| Create | dimension_003.zip    | 131,419.1 us |   810.15 us |   757.81 us | 184.28 MB |
| Create | dimension_008.zip    | 104,615.3 us |   380.61 us |   317.83 us | 124.25 MB |
| Create | dimension_033.zip    | 143,935.7 us |   427.65 us |   357.11 us | 162.89 MB |
| Create | uscensus2000.zip     |     489.7 us |     1.95 us |     1.73 us |   1.11 MB |
| Create | weath(...)t.zip [23] | 666,313.1 us | 4,932.45 us | 4,372.48 us | 637.36 MB |
| Create | weather_sept_85.zip  | 545,422.4 us | 2,982.58 us | 2,328.60 us | 511.32 MB |
| Create | wikil(...)t.zip [26] |   9,984.2 us |    32.11 us |    28.47 us |  12.76 MB |
| Create | wikil(...)s.zip [22] |  10,433.0 us |    42.52 us |    33.19 us |  12.23 MB |

After

| Method | FileName             | Mean         | Error       | StdDev      | Allocated   |
|------- |--------------------- |-------------:|------------:|------------:|------------:|
| Create | census-income.zip    |  72,622.8 us | 1,272.57 us | 1,190.36 us | 42102.72 KB |
| Create | census1881_srt.zip   |   6,658.0 us |   128.93 us |   143.31 us |  4406.49 KB |
| Create | census1881_srt.zip   |   6,562.0 us |    26.92 us |    22.48 us |  4406.39 KB |
| Create | census1881.zip       |   8,383.3 us |    87.51 us |    73.08 us |  6127.71 KB |
| Create | dimension_003.zip    |  31,738.7 us |   131.14 us |   116.26 us | 29867.13 KB |
| Create | dimension_008.zip    |  25,979.5 us |   126.73 us |    98.94 us | 19712.22 KB |
| Create | dimension_033.zip    |  38,375.0 us |   208.32 us |   194.86 us | 24818.25 KB |
| Create | uscensus2000.zip     |     106.4 us |     0.97 us |     0.86 us |   309.12 KB |
| Create | weath(...)t.zip [23] | 169,834.2 us | 3,011.43 us | 2,351.13 us | 98784.34 KB |
| Create | weather_sept_85.zip  | 131,347.5 us |   497.40 us |   440.93 us | 78654.95 KB |
| Create | wikil(...)t.zip [26] |   2,493.9 us |    14.76 us |    11.52 us |  2038.13 KB |
| Create | wikil(...)s.zip [22] |   1,973.9 us |    11.19 us |     9.92 us |  1854.96 KB |

The results are so much better in all aspects that I think we can even drop the CreateOld tests and merge (it was interesting to have them nonetheless to ensure we had no regression)

[mitikov]

@ogxd cool, gogogogo

[ogxd]

Merged. I just published a new version: https://www.nuget.org/packages/Equativ.RoaringBitmaps/0.1.5