support zc.recipe.egg:script recipe

it's just an alias for zc.recipe.egg or zc.recipe.egg:scripts

nxdbom/__init__.py

@@ -190,7 +190,7 @@ def bom_software(installed_software_path): # -> {} (name,kind) -> PkgInfo
             if isegg:                   # ignore .egg-link - we declare it through the place
                 addbom(eggpath, 'egg')  # from where destination is downloaded from
 
-        elif recipe in ('zc.recipe.egg', 'zc.recipe.egg:eggs', 'zc.recipe.egg:scripts'):
+        elif recipe in ('zc.recipe.egg', 'zc.recipe.egg:eggs', 'zc.recipe.egg:script', 'zc.recipe.egg:scripts'):
             # zc.recipe.egg:* installs
             #   1) eggs, that are explicitly specified,
             #   2) indirect dependencies of eggs from "1", and

nxdbom/nxdbom_test.py

@@ -223,6 +223,20 @@ eggs = pygolang
 pygolang                     0.1        https://pypi.org/project/pygolang/0.1/
 """)
 
+case1("""\
+[manpy]
+recipe = zc.recipe.egg:script
+_d = /ROOT/develop-eggs
+_e = /ROOT/eggs
+__buildout_installed__ =
+eggs = dream
+initialization = # pulp needs glpk in $PATH
+	import os
+	os.environ['PATH'] = '...'
+-- /ROOT/develop-eggs/dream.egg-link --
+""", '')
+
+
 # no `eggs =`
 case1("""\
 [selenium]