Bootstrap:

- new command 'modbuild' to build modules
- separate bootstrapping from other build-blocks
- review BASH libraries
- adapt build-blocks in bootstrapping

Bootstrap/coreutils/build

@@ -1,10 +1,10 @@
-#!/usr/bin/env pbuild
+#!/usr/bin/env modbuild
 
-pmodules.configure() {
+pbuild::configure() {
     "${MODULE_SRCDIR}"/configure \
 		      --prefix="${PREFIX}" \
 	|| exit 1
 }
 
-pmodules.add_to_group 'Tools'
-pmodules.make_all
+pbuild::add_to_group 'Tools'
+pbuild::make_all