Fixed conversion warnings
Fixed warnings: Block implicitly retains 'self'; explicitly mention 'self' to indicate this is intended behavior
Fixed warnings: Method parameter of type 'NSError *__autoreleasing *' with no explicit ownership
Fixed warnings: deprecated consts
Fixed warnings: deprecated sizeWithFont methods:
- `sizeWithFont:` deprecated in iOS7, suggests usage of `sizeWithAttributes:`, but this is only available in iOS7. Created a method `UV_sizeWithFont:` that decides which method is available and uses it
- `sizeWithFont:constrainedToSize:lineBreakMode:` deprecated in iOS7, suggests usage of `boundingRectWithSize:options:attributes:context:`, but this is only available in iOS7. Created a method `UV_sizeWithFont:constrainedToSize:lineBreakMode:` that decides which method is available and uses it
Fixed warnings: incompatible pointer types sending (caused by lastObject returning id)
Fixed conversion warnings
Enabled a bunch of compiler warnings to be able to get those warnings in time
As suggested by @austintaylor in #273, replaced the NSString category with 2 methods added in `UVUtils`
Merge pull request #273 from bpoplauschi/fixed_warnings

Fixed warnings