[build] Enable building the dev-tools for functional tests

- Factor out the dev-tools into a stand-alone, no-installed program
- Built the dev-tools if --enable-testing is specified
- Remove the --enable-dev-tools configure option
- Allow suffix on the binary name
- Update symlinks
- Cleanup Makefile

era/devel_commands.cc

@@ -0,0 +1,12 @@
+#include "era/commands.h"
+
+using namespace base;
+
+//----------------------------------------------------------------
+
+void
+era::register_era_commands(base::application &app)
+{
+}
+
+//----------------------------------------------------------------