Update to latest of semver 2.x

deduce.go

@@ -268,7 +268,7 @@ func (m gopkginDeducer) deduceSource(p string, u *url.URL) (maybeSource, error)
 	} else {
 		u.Path = path.Join(v[2], v[3])
 	}
-	major, err := strconv.ParseInt(v[4][1:], 10, 64)
+	major, err := strconv.ParseUint(v[4][1:], 10, 64)
 	if err != nil {
 		// this should only be reachable if there's an error in the regex
 		return nil, fmt.Errorf("could not parse %q as a gopkg.in major version", v[4][1:])

maybe_source.go

@@ -100,7 +100,7 @@ type maybeGopkginSource struct {
 	// the actual upstream URL - always github
 	url *url.URL
 	// the major version to apply for filtering
-	major int64
+	major uint64
 }
 
 func (m maybeGopkginSource) try(cachedir string, an ProjectAnalyzer) (source, string, error) {

solve_basic_test.go

@@ -946,7 +946,7 @@ var basicFixtures = map[string]basicFixture{
 	},
 	"no version that matches requirement": {
 		ds: []depspec{
-			mkDepspec("root 0.0.0", "foo >=1.0.0, <2.0.0"),
+			mkDepspec("root 0.0.0", "foo ^1.0.0"),
 			mkDepspec("foo 2.0.0"),
 			mkDepspec("foo 2.1.3"),
 		},

source_test.go

@@ -125,7 +125,7 @@ func TestGopkginSourceInteractions(t *testing.T) {
 		}
 	}
 
-	tfunc := func(opath, n string, major int64, evl []Version) {
+	tfunc := func(opath, n string, major uint64, evl []Version) {
 		un := "https://" + n
 		u, err := url.Parse(un)
 		if err != nil {

vcs_source.go

@@ -281,7 +281,7 @@ func (s *gitSource) doListVersions() (vlist []Version, err error) {
 // according to the input URL.
 type gopkginSource struct {
 	gitSource
-	major int64
+	major uint64
 }
 
 func (s *gopkginSource) listVersions() (vlist []Version, err error) {