DO NOT MERGE: dummy depends package for DEMO

This shows that the _env settings in depends only applies to the first
in a chain of commands.

Test with:

    make -C depends dummy_configured

It will error out because FOO does not exist

depends/packages/dummy.mk

@@ -0,0 +1,13 @@
+package=dummy
+$(package)_version=3320100
+$(package)_download_path=https://sqlite.org/2020/
+$(package)_file_name=sqlite-autoconf-$($(package)_version).tar.gz
+$(package)_sha256_hash=486748abfb16abd8af664e3a5f03b228e5f124682b0c942e157644bf6fff7d10
+
+define $(package)_set_vars
+  $(package)_config_env+=FOO=BAR
+endef
+
+define $(package)_config_cmds
+  true && echo 'Attempting to print FOO env var' && printenv FOO && echo "FOO was just printed"
+endef

depends/packages/packages.mk

@@ -1,4 +1,4 @@
-packages:=boost libevent
+packages:=boost libevent dummy
 
 qrencode_packages = qrencode