transam README small fix

Hi,

Transaction function call sequence description in transam/README is slightly outdated. Select now handled by PortalRunSelect instead of ProcessQuery. It is also hard to follow what tabulation there means — sometimes that means “function called by function”, sometimes it isn't. So I’ve also changed it to actual call nesting.



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Stas Kelvich
Postgres Professional: http://www.postgrespro.com
Russian Postgres Company