Change to using trunk of github/libgit2/libgit2, and use a separate target to update it and build it from within Xcode

Author: Rowan James

.gitmodules

@@ -1,3 +1,3 @@
 [submodule "libgit2"]
-    path = libgit2
-    url = http://github.com/pieter/libgit2.git
+	path = libgit2
+	url = https://github.com/libgit2/libgit2.git

GitX.xcodeproj/project.pbxproj

@@ -11,7 +11,7 @@
 #import "PBGitLane.h"
 #import "PBGitGraphLine.h"
 #import <list>
-#import "git/oid.h"
+#import <git2/oid.h>
 #include <algorithm>
 
 using namespace std;

PBGitGrapher.mm

@@ -6,7 +6,7 @@
 //  Copyright 2008 __MyCompanyName__. All rights reserved.
 //
 #import <Cocoa/Cocoa.h>
-#include "git/oid.h"
+#include <git2/oid.h>
 
 class PBGitLane {
 	static int s_colorIndex;
@@ -24,7 +24,7 @@ class PBGitLane {
 
 	PBGitLane(NSString *sha)
 	{
-		git_oid_mkstr(&d_sha, [sha UTF8String]);
+		git_oid_fromstr(&d_sha, [sha UTF8String]);
 		d_index = s_colorIndex++;
 	}
 

PBGitLane.h

@@ -148,7 +148,7 @@ - (void) walkRevisionListWithSpecifier:(PBGitRevSpecifier*)rev
 		}
 
 		git_oid oid;
-		git_oid_mkstr(&oid, sha.c_str());
+		git_oid_fromstr(&oid, sha.c_str());
 		PBGitCommit *newCommit = [PBGitCommit commitWithRepository:repository andSha:[PBGitSHA shaWithOID:oid]];
 
 		string author;

PBGitRevList.mm

@@ -7,7 +7,7 @@
 //
 
 #import <Cocoa/Cocoa.h>
-#include "git/oid.h"
+#include <git2/oid.h>
 
 
 @interface PBGitSHA : NSObject <NSCopying> {

PBGitSHA.h

@@ -8,6 +8,7 @@
 
 #import "PBGitSHA.h"
 
+#import <git2/errors.h>
 
 @interface PBGitSHA ()
 
@@ -32,7 +33,7 @@ + (PBGitSHA *)shaWithOID:(git_oid)oid
 + (PBGitSHA *)shaWithString:(NSString *)shaString
 {
 	git_oid oid;
-	int err = git_oid_mkstr(&oid, [shaString UTF8String]);
+	int err = git_oid_fromstr(&oid, [shaString UTF8String]);
 	if (err == GIT_ENOTOID)
 		return nil;
 
@@ -43,7 +44,7 @@ + (PBGitSHA *)shaWithString:(NSString *)shaString
 + (PBGitSHA *)shaWithCString:(const char *)shaCString
 {
 	git_oid oid;
-	int err = git_oid_mkstr(&oid, shaCString);
+	int err = git_oid_fromstr(&oid, shaCString);
 	if (err == GIT_ENOTOID)
 		return nil;