Added showvars utility class for debugging.

Class can be added to any recipe and will create a target
called 'showvars' which will dump out all of the variable
values in a much simpler list than 'bitbake -e'

meta-citadel-distro/classes/showvars.bbclass

@@ -0,0 +1,17 @@
+
+addtask showvars
+
+do_showvars[nostamp] = "1"
+
+python do_showvars() {
+    # emit only the metadata that are variables but not functions
+    isfunc = lambda key: bool(d.getVarFlag(key, 'func'))
+    vars = sorted((key for key in bb.data.keys(d) if not key.startswith('__')))
+    for var in vars:
+        if not isfunc(var):
+            try:
+                val = d.getVar(var, True)
+            except Exception as exc:
+                bb.plain('Expansion of %s threw %s: %s' % (var, exc.__class__.__name__, str(exc)))
+            bb.plain('%s="%s"' % (var,val))
+}

meta-citadel-distro/recipes-misc/showvars/showvars.bb

@@ -0,0 +1,17 @@
+
+SUMMARY = "Display variables"
+LICENSE = "MIT"
+
+
+INHIBIT_DEFAULT_DEPS = "1"
+PACKAGES = ""
+
+deltask do_fetch
+deltask do_unpack
+deltask do_patch
+deltask do_configure
+deltask do_compile
+deltask do_install
+deltask do_populate_sysroot
+
+inherit showvars nopackages