hashdist: Add easylogging++ package.

Author: memmett

tools/hashdist/pkgs/easylogging.yaml

@@ -0,0 +1,12 @@
+extends: [base_package]
+
+sources:
+- key: zip:dy4xizoferpseti6ooa7czlbf3irm574
+  url: https://github.com/easylogging/easyloggingpp/releases/download/v9.77/easyloggingpp_v9.77.zip
+
+build_stages:
+- name: install
+  handler: bash
+  bash: |
+    mkdir ${ARTIFACT}/include
+    cp easylogging++.h ${ARTIFACT}/include