Always show size with 2 decimal places

Prevents the decimal precision display jumping around when progress is updated
minor #50 Always show size with 2 decimal places (elliot)

This PR was merged into the 1.0-dev branch.

Discussion
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Always show size with 2 decimal places

Prevents the decimal precision display jumping around when progress is updated

Commits
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03aaaa0 Always show size with 2 decimal places