Observable benchmarks

These benchmarks can be found at https://github.com/TylorS/most/tree/master/test/perf
Hopefully they will get merged into the most.js repo itself.
To keep up with that, the PR is here: https://github.com/cujojs/most/pull/172

Versions
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Node     - 5.1.0
Most     - 0.16.0
Rx 4     - 4.0.7
Rx 5     - 5.0.0-alpha.12
Kefir    - 3.1.0
Bacon    - 0.7.82
Highland - 2.5.1
Lodash   - 3.10.1
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concatMap 1000 x 1000 streams
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most        156.13 op/s ±  0.58%   (82 samples)
rx 4          1.28 op/s ±  2.95%    (8 samples)
rx 5          7.33 op/s ±  6.83%   (22 samples)
kefir        11.75 op/s ±  3.13%   (32 samples)
bacon         0.90 op/s ±  7.03%    (7 samples)
lodash       31.24 op/s ±  4.79%   (52 samples)
Array         0.78 op/s ±  4.38%    (7 samples)
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filter -> map -> reduce 1000000 integers
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most        377.69 op/s ±  2.07%   (83 samples)
rx 4          1.28 op/s ±  3.80%    (8 samples)
rx 5          4.55 op/s ±  7.80%   (15 samples)
kefir        10.29 op/s ±  7.86%   (28 samples)
bacon         1.18 op/s ±  1.78%    (7 samples)
highland      6.25 op/s ±  7.73%   (19 samples)
lodash      111.57 op/s ±  3.35%   (65 samples)
Array         8.34 op/s ±  2.69%   (25 samples)
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flatMap 1000 x 1000 streams
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most        193.95 op/s ±  0.47%   (88 samples)
rx 4          0.80 op/s ±  3.37%    (6 samples)
rx 5          6.41 op/s ±  9.71%   (19 samples)
kefir         9.79 op/s ± 10.09%   (28 samples)
bacon         0.98 op/s ±  4.37%    (7 samples)
highland      0.20 op/s ±  5.08%    (5 samples)
lodash       34.22 op/s ±  2.92%   (55 samples)
Array         0.76 op/s ±  1.75%    (6 samples)
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scan -> reduce 1000000 integers
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most        341.98 op/s ±  0.65%   (87 samples)
rx 4          1.27 op/s ±  2.84%    (8 samples)
rx 5          4.19 op/s ±  7.18%   (15 samples)
kefir        15.87 op/s ± 11.75%   (26 samples)
bacon         0.89 op/s ±  4.96%    (7 samples)
highland      5.04 op/s ±  9.09%   (17 samples)
lodash       47.75 op/s ±  4.05%   (50 samples)
Array         6.93 op/s ±  4.89%   (22 samples)
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skipRepeats -> reduce 2 x 1000000 integers
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most        406.64 op/s ±  0.72%   (84 samples)
rx 4          1.51 op/s ±  6.52%    (8 samples)
rx 5          5.36 op/s ± 10.15%   (17 samples)
kefir        10.49 op/s ± 10.20%   (29 samples)
bacon         1.31 op/s ±  4.01%    (8 samples)
lodash      120.19 op/s ±  2.41%   (69 samples)
Array        10.90 op/s ±  1.68%   (31 samples)
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zip 2 x 100000 integers
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most        133.48 op/s ±  1.13%   (87 samples)
rx 4          3.75 op/s ±  7.31%   (13 samples)
rx 5         17.79 op/s ±  9.35%   (26 samples)
kefir        13.64 op/s ±  9.39%   (35 samples)
bacon         1.32 op/s ±  6.55%    (8 samples)
highland      0.61 op/s ±  6.67%    (6 samples)
lodash       38.75 op/s ± 11.51%   (51 samples)
-------------------------------------------------------