Cleanup stdlib docs

[jolestar]

Pull request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

What is the current behavior?

mv documents to starcoin-framework starcoinorg/starcoin-framework#21

Issue Number: N/A

What is the new behavior?

Other information

[github-actions]

Benchmark for efd22e9

Click to view benchmark

Test	Base	PR	%
accumulator_append	588.7±11.53µs	586.4±10.80µs	-0.39%
block_apply/block_apply_10	266.6±0.80ms	265.8±0.60ms	-0.30%
block_apply/block_apply_1000	27.3±0.01s	27.1±0.02s	-0.73%
get_with_proof/db_store	36.0±0.33µs	35.9±0.38µs	-0.28%
get_with_proof/mem_store	31.3±0.32µs	31.1±0.26µs	-0.64%
put_and_commit/db_store/1	96.2±9.13µs	94.6±4.75µs	-1.66%
put_and_commit/db_store/10	851.6±39.44µs	852.9±39.43µs	+0.15%
put_and_commit/db_store/100	7.4±0.37ms	7.3±0.35ms	-1.35%
put_and_commit/db_store/5	432.5±21.73µs	436.2±21.79µs	+0.86%
put_and_commit/db_store/50	3.8±0.17ms	3.8±0.17ms	0.00%
put_and_commit/mem_store/1	61.0±5.56µs	61.4±5.44µs	+0.66%
put_and_commit/mem_store/10	570.4±45.09µs	576.0±46.86µs	+0.98%
put_and_commit/mem_store/100	5.6±0.33ms	5.6±0.79ms	0.00%
put_and_commit/mem_store/5	288.3±23.40µs	290.8±24.87µs	+0.87%
put_and_commit/mem_store/50	2.8±0.08ms	2.8±0.18ms	0.00%
query_block/query_block_in(10)_times(100)	3.8±0.13ms	3.8±0.12ms	0.00%
query_block/query_block_in(10)_times(1000)	38.3±1.32ms	38.8±0.74ms	+1.31%
query_block/query_block_in(10)_times(10000)	383.2±5.43ms	387.2±9.19ms	+1.04%
query_block/query_block_in(1000)_times(100)	953.1±6.87µs	954.3±5.99µs	+0.13%
query_block/query_block_in(1000)_times(1000)	9.5±0.06ms	9.6±0.07ms	+1.05%
query_block/query_block_in(1000)_times(10000)	95.5±0.94ms	95.5±0.48ms	0.00%
storage_transaction	1045.6±270.31µs	1044.7±276.33µs	-0.09%
vm/transaction_execution/1	315.1±1.01ms	314.3±0.87ms	-0.25%
vm/transaction_execution/10	100.0±2.76ms	98.4±0.29ms	-1.60%
vm/transaction_execution/20	91.0±0.30ms	90.6±0.19ms	-0.44%
vm/transaction_execution/5	121.1±0.41ms	120.8±0.46ms	-0.25%
vm/transaction_execution/50	102.9±0.83ms	102.8±1.72ms	-0.10%

[xudon9]

Looks good. All changes are about removing generated stdlib docs and related doc generation code.