Uses consistent property declarations throughout the project

All properties are nonatomic, unless there is a reason for them to be atomic (currently not the case in any file)
Blocks are declared using 'copy', as recommended by Apple: https://developer.apple.com/library/ios/documentation/cocoa/conceptual/ProgrammingWithObjectiveC/WorkingwithBlocks/WorkingwithBlocks.html#//apple_ref/doc/uid/TP40011210-CH8-SW12
Do not specify default attributes, such as, 'strong' for object references
Merge pull request #8 from iosphere/pullRequest/propertyDeclarations

Uses consistent property declarations throughout the project