Fixes FT #6721 - Saves time as UTC.
Merge pull request #125 from adamruzicka/fixes-ft-6721

Fixes FT #6721 - Saves time as UTC
Deserialize the time into UTC instead of local time
Ensure the execution finishes before proceeding to other test

Fixes random issues with TestExecutionLog
Do not use simple world for testing

The simple world tries to resume planned plans when creating new
world. In tests, it introduces some undeterminism and causes tests to
fail at some seeds.
Merge pull request #126 from iNecas/fix-timezones

Deserialize the time into UTC instead of local time
Bump version
Ensure deserialization from json keeps numeric values

After Oj 2.10.0, there happens quite often that the float is
deserialized to BigDecimal which is serialized back to string.

    MultiJson.load(MultiJson.dump(
      MultiJson.load(MultiJson.dump(6.903916489999999))))
    # => "6.903916489999999"

Also, other JSON implementations have similar behavior when it takes
BigDecimal. More details here https://github.com/ohler55/oj/pull/59.

As preserving of the float type is not guaranteed, we need to manually
typecast to_f to avoid

   Value (String) '3.00232023232032203232' is not any of: Numeric; NilClass
Merge pull request #127 from iNecas/fix-float-deserialize

Ensure deserialization from json keeps numeric values
Bump version
Stop planning right after some error occurred