add configuration file for istanbul

.istanbul.yml

@@ -0,0 +1,46 @@
+verbose: false
+instrumentation:
+  root: lib
+  extensions:
+    - .ts
+#   default-excludes: true
+#   excludes: []
+#   variable: __coverage__
+#   compact: true
+#   preserve-comments: false
+#   complete-copy: false
+#   save-baseline: false
+#   baseline-file: ./coverage/coverage-baseline.raw.json
+#   include-all-sources: false
+#   include-pid: false
+#   es-modules: true
+#   auto-wrap: true
+# reporting:
+#   print: summary
+#   reports:
+#     - lcov
+#   dir: ./coverage
+#   summarizer: pkg
+#   report-config: {}
+#   watermarks:
+#     statements: [50, 80]
+#     functions: [50, 80]
+#     branches: [50, 80]
+#     lines: [50, 80]
+# hooks:
+#   hook-run-in-context: false
+#   post-require-hook: null
+#   handle-sigint: false
+# check:
+#   global:
+#     statements: 0
+#     lines: 0
+#     branches: 0
+#     functions: 0
+#     excludes: []
+#     each:
+#       statements: 0
+#       lines: 0
+#       branches: 0
+#       functions: 0
+#       excludes: []