Use semver.parse() instead of semver()

It seems that newer versions (>= v7.0.0) of the semver module have
dropped support for calling it as semver(<version>), so switching to
semver.parse(<version>) makes the code ready for a future upgrade to
a more current version of the semver module.

Author: mstock

index._

@@ -34,7 +34,7 @@ var getSatisfyingVersion = function (wanted) {
     var version = semver.maxSatisfying(versions, wanted), parsed;
     if (!version) {
         try {
-            parsed = semver(wanted);
+            parsed = semver.parse(wanted);
             parsed.patch = 'x';
             version = semver.maxSatisfying(versions, parsed.format());
         } catch (err) {

index.js

@@ -38,7 +38,7 @@ var getSatisfyingVersion = function (wanted) {
     var version = semver.maxSatisfying(versions, wanted), parsed;
     if (!version) {
         try {
-            parsed = semver(wanted);
+            parsed = semver.parse(wanted);
             parsed.patch = 'x';
             version = semver.maxSatisfying(versions, parsed.format());
         } catch (err) {