initial commit for LGError Class

Basic error class to simplify populating of NSError objects.
Built to be expanded to fit the Error handling needs as development progresses.

Example Usage:
```Objective-c
NSError *error;
if ([LGError errorWithTaskError:aTask verb:kLGAutoPkgrRun error:&error]) {
    // if this returns YES an error has occurred log it...       
    NSLog(@"%@",error.localizedDescription);
}

```
LGError.h
```Objective-c
+ (BOOL)errorWithCode:(LGErrorCodes)code error:(NSError **)error;
/**
 *  Generate an NSError Object for AutoPkgr
 *
 *  @param code  cooresponging LGErrorCodes
 *
 *  @return Populated NSError Object if error code is != kLGErrorSuccess, nil otherwise;
 */
+ (NSError *)errorWithCode:(LGErrorCodes)code;

#pragma mark - NSTask Error
/**
 *  Populate an NSError using a completed NSTask
 *
 *  @param task  Completed NSTask Object
 *  @param verb  Cooresponding Action Word Describing the AutoPkgr task process
 *  @param error __autoreleasing NSError object
 *
 *  @return YES if Error has occured, NO if error.code = kLGErrorSuccess.
 *  @discussion If the task is not complete the error will return NO;
 */
+ (BOOL)errorWithTaskError:(NSTask *)task verb:(LGAutoPkgrVerb)verb error:(NSError **)error;
/**
 *  Generated NSError Object from and AutoPkgr NSTask
 *
 *  @param task  Completed NSTask Object
 *  @param verb  Cooresponding Action Word Describing the AutoPkgr task process
 *
 *  @return Populated NSError Object if exit status is != kLGErrorSuccess, nil otherwise;
 *  @discussion If the returned object will be nil if the task has not complete;
 */
+ (NSError *)errorWithTaskError:(NSTask *)task verb:(LGAutoPkgrVerb)verb;

```

This commit contains changes to the error handling in LGAutoPkgRunner Class' autopkg tasks


__The class also contains a new function__
```
DLog(format,...)
```
This can be used exactly like NSLog but it only logs messages when running a debug build.  This will help reduce the amount of information logged in release builds.