Lazily creating the FLEXWindow when it's actually needed.

This allows users of FLEXManager to use the -registerGlobalEntryWithName:objectFutureBlock: API in a +load method of their app. Right now that creates the UIWindow object when UIKit is not ready. With this change, the window will be created the first time you call -showExplorer, which would also help a bit with launch times in apps that have FLEX because creating that object would be delayed from app launch to the first time it's used.
Add FLEXFloor macro for retina aware rounding.

This allows us to move views to 0.5 point origin values on retina devices.
Also create the explorer view controller lazily.
Eliminate ambiguity when using the property, ivar, and method boxes.

Some users have reported build errors in these areas. They likely have conflicting methods that get imported through a PCH. For example, if the compiler sees a definition of another method called “property” that returns an NSString, it doesn’t know which one to pick.
Merge pull request #14 from JaviSoto/feature/lazy-window-creation

Lazily creating the FLEXWindow when it's actually needed.
Don't rely on UIKit.h being imported from a PCH
Rename variables in inner scope to avoid shadowing outer variables of the same name.

Discovered with -Wshadow
Search bar filtering and sorting by file size in the file browser
Merge pull request #15 from DaidoujiChen/develop

Search bar filtering and sorting by file size in the file browser
Update changes and todo sections in the README
Fix “dead store” warning from the clang static analyzer.

We only use fullPath later. Subpath is only used temporarily to build the fullPath in one of the cases.
Use explicit nil initialization for consistency within the project.
when press "Search" button, searchBar need to resignFirstResponder
Merge pull request #22 from DaidoujiChen/develop

Hide keyboard when search button is pressed
add a default File Browser
Merge pull request #23 from studentdeng/develop

add a default File Browser
Add installation section to README
Respect child view controller status bar forwarding
Bump version in podspec
Remove "Changes" section from README

Replaced by Github's releases feature.