Initial work on 1.13 forge resolver, fixes.

Moved java executable to its own util class.
Fixed artifact resolution links for older versions of forge.

1.13 support is going to be difficult because forge does not
make anything developer friendly.

src/model/forge/versionmanifest.ts

@@ -14,7 +14,8 @@ export interface VersionManifest {
         url?: string,
         checksums?: string[],
         serverreq?: boolean,
-        clientreq?: boolean
+        clientreq?: boolean,
+        comment?: string
     }>
 
 }

src/model/struct/model/server.struct.ts

@@ -103,7 +103,7 @@ export class ServerStructure extends BaseModelStructure<Server> {
                 const forgeResolver = ResolverRegistry.getForgeResolver(
                     match[2],
                     serverMeta.forgeVersion,
-                    dirname(this.absoluteRoot),
+                    dirname(this.containerDirectory),
                     '',
                     this.baseUrl
                 )

src/model/struct/repo/repo.struct.ts

@@ -43,4 +43,8 @@ export class RepoStructure extends BaseFileStructure {
         return join(this.absoluteRoot, 'temp')
     }
 
+    public getWorkDirectory() {
+        return join(this.absoluteRoot, 'work')
+    }
+
 }