adding new ceedling test project

test/vendor/ceedling/plugins/subprojects/README.md

@@ -0,0 +1,63 @@
+ceedling-subprojects
+====================
+
+Plugin for supporting subprojects that are built as static libraries. It continues to support  
+dependency tracking, without getting confused between your main project files and your   
+subproject files. It accepts different compiler flags and linker flags, allowing you to   
+optimize for your situation.
+
+First, you're going to want to add the extension to your list of known extensions:
+
+```
+:extension:
+  :subprojects: '.a'
+```
+
+Define a new section called :subprojects. There, you can list as many subprojects  
+as you may need under the :paths key. For each, you specify a unique place to build  
+and a unique name.
+
+```
+:subprojects:  
+  :paths:
+   - :name: libprojectA
+     :source:
+       - ./subprojectA/first/dir
+       - ./subprojectA/second/dir
+     :include:
+       - ./subprojectA/include/dir
+     :build_root: ./subprojectA/build/dir
+     :defines: 
+       - DEFINE_JUST_FOR_THIS_FILE
+       - AND_ANOTHER
+   - :name: libprojectB
+     :source:
+       - ./subprojectB/only/dir
+     :include:
+       - ./subprojectB/first/include/dir
+       - ./subprojectB/second/include/dir
+     :build_root: ./subprojectB/build/dir
+     :defines: [] #none for this one
+```
+
+You can specify the compiler and linker, just as you would a release build:
+
+```
+:tools:
+  :subprojects_compiler:
+    :executable: gcc
+    :arguments:
+      - -g
+      - -I"$": COLLECTION_PATHS_SUBPROJECTS
+      - -D$: COLLECTION_DEFINES_SUBPROJECTS
+      - -c "${1}"
+      - -o "${2}"
+  :subprojects_linker:
+    :executable: ar
+    :arguments:
+      - rcs
+      - ${2}
+      - ${1}
+```
+
+That's all there is to it! Happy Hacking!