Refactor qck_ macros into functions
Rename Objective-C it/itBehavesLike methods

Avoids conflicts with the `it` and `itBehavesLike` macros.
Unfortunately, using QUICK_DISABLE_SHORT_SYNTAX doesn’t help here,
since consumers will probably (intentionally or not) import the
World+DSL header in Objective-C.
Refactor macro aliases as static inline functions

This avoids naive text replacement when the keywords are encountered in
(say) method parameter names.

Unfortunately, it doesn’t seem to be possible to do this for `it` and
`itBehavesLike` if we want to preserve file/line information.
Add newline to itBehavesLike test, for breakpoints
Fix tabs -> spaces
Rename void block typedef to QCKDSLEmptyBlock
Clarify what might conflict with shorthand syntax
Merge pull request #185 from github/fix-objc-breakpoints

Fix breakpoints in Objective-C