Refactoring docs about environment
Changing text order to better details about priority
Portuguese text only
Better text in english
Fixing some typo
Adding info about getOrDefault method
Typo and docs about getOrDefault (portuguese)
Fixing typo
Adding properties highlight
Space to tabs
Merge pull request #824 from caelum/ot-gh818-refactorenvdocs

Refactoring docs about environment