Extend the IConfig interface as needed for 3rd-party projects

In my endeavor to support projects other than Git, I am currently
adapting GitGitGadget to allow sending Cygwin PRs to the Cygwin-patches
mailing list.

I identified a couple of gaps in the project configuration when setting
up stuff in https://github.com/cygwingitgadget.

Let's close those gaps.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

Author: dscho

lib/gitgitgadget-config.ts

@@ -27,6 +27,8 @@ const defaultConfig: IConfig = {
     mail: {
         author: "GitGitGadget",
         sender: "GitGitGadget",
+        smtpUser: "gitgitgadget@gmail.com",
+        smtpHost: "smtp.gmail.com",
     },
     app: {
         appID: 12836,
@@ -42,6 +44,18 @@ const defaultConfig: IConfig = {
     user: {
         allowUserAsLogin: false,
     },
+    syncUpstreamBranches: [
+        {
+            sourceRepo: "gitster/git",
+            targetRepo: "gitgitgadget/git",
+            sourceRefRegex: "^refs/heads/(maint-\\d|[a-z][a-z]/)",
+        },
+        {
+            sourceRepo: "j6t/git-gui",
+            targetRepo: "gitgitgadget/git",
+            targetRefNamespace: "git-gui/",
+        },
+    ],
 };
 
 export default defaultConfig;

lib/project-config.ts

@@ -35,6 +35,8 @@ export interface IConfig {
     mail: {
         author: string;
         sender: string;
+        smtpUser: string;
+        smtpHost: string;
     };
     project?: projectInfo | undefined; // project-options values
     app: {
@@ -51,6 +53,12 @@ export interface IConfig {
     user: {
         allowUserAsLogin: boolean; // use GitHub login as name if name is private
     };
+    syncUpstreamBranches: Array<{
+        sourceRepo: string; // e.g. "gitster/git"
+        targetRepo: string; // e.g. "gitgitgadget/git"
+        sourceRefRegex?: string; // e.g. "^refs/heads/(maint-\\d|[a-z][a-z]/)"
+        targetRefNamespace?: string; // e.g. "git-gui/"
+    }>; // branches to sync from upstream to our repo
 }
 
 let config: IConfig; // singleton