Misc fixes

[bertoldia]

Hi there, This branch contains a few misc fixes:

• retab and remove trailing whitespaces
• refactor temper.c
• use ISO 8601 date/time format
• user errno instead of reading value and number of read attempts to indicate no successful reads.

I think the change-set is best viewed by looking at the commits instead of the diff since the retab touches everything.

Thanks.