Move FBScubaSample to swift

Summary: This is the first step in moving our logging stack to swift. Some of the code will be added or *slightly* updated in future diffs in the stack, because it is require proper bridging to be setted up and I don't need that cause I reimplemented other parts on swift in future diffs

Reviewed By: jbardini

Differential Revision: D36625231

fbshipit-source-id: 3c6ce5599ebdda0747fbb55d5bcd073287bb4d8d

FBControlCore/Utility/FBXcodeConfiguration.h

@@ -86,7 +86,7 @@ NS_ASSUME_NONNULL_BEGIN
 /**
  Return Developer directory if exist or nil.
  */
-+ (NSString *)getDeveloperDirectoryIfExists;
++ (nullable NSString *)getDeveloperDirectoryIfExists;
 
 @end
 

FBControlCore/Utility/FBXcodeConfiguration.m

@@ -22,7 +22,7 @@
   return [self findXcodeDeveloperDirectoryOrAssert];
 }
 
-+ (NSString *)getDeveloperDirectoryIfExists
++ (nullable NSString *)getDeveloperDirectoryIfExists
 {
   return [self findXcodeDeveloperDirectoryFromXcodeSelect:nil];
 }
@@ -160,7 +160,7 @@
   return directory;
 }
 
-+ (NSString *)findXcodeDeveloperDirectoryFromXcodeSelect:(NSError **)error
++ (nullable NSString *)findXcodeDeveloperDirectoryFromXcodeSelect:(NSError **)error
 {
   static dispatch_once_t onceToken;
   static NSString *directory;

idb_companion/Bridging/idb_companion-Bridging-Header.h

@@ -24,3 +24,4 @@
 
 // Configuration
 #import "../Configuration/FBIDBPortsConfiguration.h"
+#import "../Configuration/FBIDBConfiguration.h"