Integrate Crashpad crash handler into CApplication

Crash handler launches an external crash handler executable called
swift_crashpad_handler. It monitores the parent process and produces
a local dump in case of a crash.
For release builds, the dump is also uploaded to a crash report server.

refs #490

resources/share/shared/bootstrap/bootstrap.json

@@ -1,4 +1,7 @@
 {
+	"crashreportServerUrl": {
+        "url": "http://crashreports.swift-project.org:8090/crash_upload"
+    },
     "dbHttpPort": 5080,
     "dbHttpsPort": 50443,
     "dbRootDirectoryUrl": {