Add Electron Support (#199)

### Platforms affected
none


### Motivation and Context
Support for creating mobilespec builds for Electron Release process.

### Description
- Only added the necessary flags

### Testing
None

### Checklist

- [ ] I've run the tests to see all new and existing tests pass
- [ ] I added automated test coverage as appropriate for this change
- [ ] Commit is prefixed with `(platform)` if this change only applies to one platform (e.g. `(android)`)
- [ ] If this Pull Request resolves an issue, I linked to the issue in the text above (and used the correct [keyword to close issues using keywords](https://help.github.com/articles/closing-issues-using-keywords/))
- [ ] I've updated the documentation if necessary


diff --git a/createmobilespec/createmobilespec.js b/createmobilespec/createmobilespec.js
index a99ffb7..e1e547f 100755
--- a/createmobilespec/createmobilespec.js
+++ b/createmobilespec/createmobilespec.js
@@ -101,7 +101,10 @@
                                               "config": ["res", "xml"] },
                             "browser": { "bin": ["cordova-browser"],
                                               "www": ["www"],
-                                              "config": ["www"] },   
+                                              "config": ["www"] },
+                            "electron": { "bin": ["cordova-electron"],
+                                              "www": ["www"],
+                                              "config": ["www"] },
                             "ios":          { "bin": ["cordova-ios"],
                                               "www": ["www"],
                                               "config": ["CUSTOM"] },
@@ -113,12 +116,13 @@
     argv = optimist.usage("\nUsage: $0 PLATFORM... [--help] [--plugman] [--link] [--global] [--globalplugins] [--plugins=\".\\myPluginDir\"] [--skipjs] [--skiplink] [--variable VAR=\"value\"] [directoryName]\n" +
                           "A project will be created with the mobile-spec app and all the core plugins.\n" +
                           "At least one platform must be specified. See the included README.md.\n" +
-                          "\tPLATFORM: [--<android|ios|windows|osx>]\n" +
+                          "\tPLATFORM: [--<android|browser|electron|ios|osx|windows>]\n" +
                           "")
                    .boolean("help").describe("help", "Shows usage.")
                    .boolean("debug").describe("debug", "Debug logging.")
                    .boolean("android").describe("android", "Add Android platform.")
                    .boolean("browser").describe("browser", "Add Browser platform.")
+                   .boolean("electron").describe("electron", "Add Electron platform.")
                    .boolean("ios").describe("ios", "Add iOS platform.")
                    .boolean("osx").describe("osx", "Add osx platform (macOS).")
                    .boolean("windows").describe("windows", "Add Windows (universal) platform.")
@@ -205,6 +209,7 @@
 if (argv.android) { platforms.push("android"); }
 if (argv.ios) { platforms.push("ios"); }
 if (argv.browser) { platforms.push("browser"); }
+if (argv.electron) { platforms.push("electron"); }
 if (argv.windows) { platforms.push("windows"); }
 if (argv.osx) {platforms.push("osx");}