Make sure the type we use to store integer is correct and "big" enough

[pnowosie]

Fixes #129

After analysis a few columns needs bump to bigint type:

Sufficient?	table_name	column_name	data_type	numeric_precision	needs dump?
:heavy_check_mark:	blocks	id	bigint	64
:x:	blocks	nonce	integer	32	to 64
:x:	blocks	blknum	integer	32	to 64
:x:	blocks	formed_at_ethereum_height	integer	32	to 64
:x:	blocks	submitted_at_ethereum_height	integer	32	to 64
:x:	blocks	gas	integer	32	to 64
:heavy_check_mark:	blocks	attempts_counter	integer	32
:x:	listener_states	height	integer	32	to 64
:heavy_check_mark:	outputs	id	bigint	64
:heavy_check_mark:	outputs	position	bigint	64
:heavy_check_mark:	outputs	output_type	integer	32
:heavy_check_mark:	outputs	creating_transaction_id	bigint	64
:heavy_check_mark:	outputs	spending_transaction_id	bigint	64
:heavy_check_mark:	schema_migrations	version	bigint	64
:heavy_check_mark:	transactions	id	bigint	64
:heavy_check_mark:	transactions	tx_type	integer	32
:heavy_check_mark:	transactions	tx_index	integer	32
:heavy_check_mark:	transactions	block_id	bigint	64

See issue for more details.

[pnowosie]

I confirmed failing circle's steps are not related to the PR changes.

[InoMurko]

I confirmed failing circle's steps are not related to the PR changes.

Yeah, we cabbage tests haven't been ported to V2 contracts. So it's expected for them to fail.