Fixer::getLevelAsString - cache level in variable
minor #435 Fixer::getLevelAsString - cache level in variable (keradus)

This PR was squashed before being merged into the 0.5.x-dev branch (closes #435).

Discussion
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Fixer::getLevelAsString - cache level in variable

Fixer::getLevelAsString - cache level in variable.
Also add contrib level support in Fixer::getLevelAsString

Commits
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f610ded Fixer::getLevelAsString - cache level in variable