SDK: Scripts to generate plugin's skeleton code

done:
- create plugin folder structure
- manifest.json + icon.png
- copyright header
- main.cpp
- choose number of functionalities and the api to each one of them
- create src files for each functionality (APIs skeleton .h and .cpp)
- create preferences.json
- put colors into prints and clear outputs when needed
- modify src files to set preferences code
- create pakage.json
- add helper files
- use library Cmd
- reorganize functions into classes define inherits stack
- add GNU GPL to python files
- jpl merge function
- pre and post assembles
- default options plugin build
- windows build with build-plugin.py
- add build option for windows build
- generate base CMakeLists.txt and build.sh

Change-Id: Id8eb5a97fa7a51e99a0f9215835c3d5ffea630ad
GitLab: #2
diff --git a/SDK/Docs/preferenceHelper.txt b/SDK/Docs/preferenceHelper.txt
new file mode 100644
index 0000000..078c1a5
--- /dev/null
+++ b/SDK/Docs/preferenceHelper.txt
@@ -0,0 +1,44 @@
+
+Create (or Delete) a preference: PREFERENCE (-del)
+
+A preference is a internal variable that can be used upon loading or while
+running the plugin. It should be correctly formed and listed in a preferences.json
+file. Also, a preference value only can be modified during runtime if the code that
+applies the new value is within your functionality implementation. For more
+technical information, please refer to:
+https://git.jami.net/savoirfairelinux/ring-project/wikis/technical/7.-Jami-plugins .
+
+Prior continuing, and to easy the process of constructing your preferences, take your
+time to think about the list of preferences you will be needing.
+But do not worry! If you forget something you will have the oportunity to change it
+later.
+
+Example of preferences:
+    -> LIST:
+        {
+            "category" : "Streams",
+            "type": "List",
+            "key": "videostreams",
+            "title": "Streams to transform",
+            "summary": "Select video to transform",
+            "defaultValue": "0",
+            "entries": ["sent", "received"],
+            "entryValues": ["0", "1"],
+            "scope": "plugin"
+        }
+
+    -> PATH:
+        {
+            "category" : "Backgrounds",
+            "type": "Path",
+            "mimeType": "image/png",
+            "key": "background",
+            "title": "Background image",
+            "summary": "Select the image background to use",
+            "defaultValue": "data/backgrounds/background2.png",
+            "scope": "plugin, foo"
+        }
+
+For more detailed information for each of the preferences types, please specify the preference type:
+    -> preference -h list
+    -> preference -h path