Add ClearBreakpoints API

Add a test which actually triggers the mappings and fires up vimspector
with the cpptools debugger.

tests/testdata/cpp/simple.cpp

@@ -1,7 +0,0 @@
-#include <iostream>
-
-int main( int argc, char ** )
-{
-  printf( "this is a test %d", argc );
-  return 0;
-}

tests/testdata/cpp/simple/.gitignore

@@ -0,0 +1 @@
+simple

tests/testdata/cpp/simple/.vimspector.json

@@ -0,0 +1,18 @@
+{
+  "configurations": {
+    "cpptools-run": {
+      "adapter": "vscode-cpptools",
+      "configuration": {
+        "type": "cppdbg",
+        "request": "launch",
+        "program": "${workspaceRoot}/simple",
+        "args": [],
+        "cwd": "${workspaceRoot}",
+        "environment": [],
+        "externalConsole": true,
+        "stopAtEntry": true,
+        "MImode": "${VIMSPECTOR_MIMODE}"
+      }
+    }
+  }
+}

tests/testdata/cpp/simple/Makefile

@@ -0,0 +1,7 @@
+CXXFLAGS=-g -O0
+
+simple: simple.cpp
+
+clean:
+	rm -f simple
+	rm -rf simple.dSYM

tests/testdata/cpp/simple/simple.cpp

@@ -0,0 +1,18 @@
+#include <iostream>
+
+namespace
+{
+  void foo( int bar )
+  {
+    int unused;
+
+    printf( "%d\n", bar );
+  }
+}
+
+int main( int argc, char ** )
+{
+  printf( "this is a test %d\n", argc );
+  foo( argc );
+  return 0;
+}