optimization work for raster flood on roads #906
unit tests for raster flood optimization #906
Merge remote-tracking branch 'upstream/develop' into develop
Correct code style. Update impact function metadata #906
Merge pull request #907 from assefay/inasafe

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Possible optimization for raster floods on roads.
I have kept both ways for now so that It is easier to compare for validation purposes.
Code formatting and variable naming cleanups.