Compare JSON and jstp-serde

[nechaido]

I open issue per @tshemsedinov's request.
current benchmark can be found at: https://github.com/metarhia/jstp/tree/serde-comparison.
Benchmark output:

Parrsing:

string:
serde x 3,137,878 ops/sec ±1.19% (91 runs sampled)
JSON x 9,713,580 ops/sec ±3.64% (81 runs sampled)
JSON is 210% faster than serde

string with length = 1048576:
serde x 166 ops/sec ±2.53% (68 runs sampled)
JSON x 485 ops/sec ±2.56% (75 runs sampled)
JSON is 192% faster than serde

array of integers:
serde x 5,236 ops/sec ±3.53% (80 runs sampled)
JSON x 20,311 ops/sec ±2.13% (80 runs sampled)
JSON is 288% faster than serde

Marcus object:
serde x 88,024 ops/sec ±5.90% (64 runs sampled)
JSON x 398,530 ops/sec ±3.98% (81 runs sampled)
JSON is 353% faster than serde

Marcus array:
serde x 222,916 ops/sec ±1.53% (91 runs sampled)
JSON x 1,028,684 ops/sec ±1.73% (89 runs sampled)
JSON is 361% faster than serde

Marcus string:
serde x 585,653 ops/sec ±2.26% (85 runs sampled)
JSON x 2,503,146 ops/sec ±2.54% (85 runs sampled)
JSON is 327% faster than serde

Serialization:

string:
serde x 1,340,569 ops/sec ±0.98% (87 runs sampled)
JSON x 4,549,716 ops/sec ±2.06% (88 runs sampled)
JSON is 239% faster than serde

string with length = 1048576:
serde x 223 ops/sec ±2.79% (74 runs sampled)
JSON x 302 ops/sec ±1.28% (82 runs sampled)
JSON is 35% faster than serde

array of integers:
serde x 45,285 ops/sec ±0.79% (91 runs sampled)
JSON x 48,875 ops/sec ±0.94% (85 runs sampled)
JSON is 8% faster than serde

Marcus object:
serde x 481,203 ops/sec ±1.34% (89 runs sampled)
JSON x 914,241 ops/sec ±1.38% (87 runs sampled)
JSON is 90% faster than serde

Marcus array:
serde x 546,240 ops/sec ±1.84% (85 runs sampled)
JSON x 1,549,922 ops/sec ±1.41% (91 runs sampled)
JSON is 184% faster than serde

Marcus string:
serde x 462,112 ops/sec ±0.47% (92 runs sampled)
JSON x 1,137,381 ops/sec ±0.77% (91 runs sampled)
JSON is 146% faster than serde