Add a README

Author: timholy

README.md

@@ -3,5 +3,32 @@
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+
+A package to create simple "module docstrings" for Julia packages. These are targeted at summarizing the main components of your package, essentially as a prompt or reminder to users.  For example:
+
+```julia
+julia> using ModuleDocstrings
+
+help?> ModuleDocstrings
+search: ModuleDocstrings
+
+    •  ModuleDocstrings.generate: Create an API summary docstring for a
+       module.
+
+    •  ModuleDocstrings.write: add an API summary docstring to a package.
+```
+
+Then, to learn more about `generate`:
+
+```julia
+help?> ModuleDocstrings.generate
+  ModuleDocstrings.generate(mod::Module)
+
+  Return an API summary string for mod.
+
+  The summary is assembled from all docstrings in the package, picking the
+  first sentence of each docstring. Expect to need to edit these by hand to
+  produce something truly useful.
+
+```