add rudimentary unit tests, and logging timestamps

Signed-off-by: Aidan Hahn <aidan@aidanis.online>

README.md

@@ -1,13 +1,28 @@
 # Introduction
 - *alog* or *a logger* is a lightweight, portable logger written in C.
 - It is entirely unremarkable
-- Usage of *alog* is extremely simple. [See the API](alog.h)
+- Usage of *alog* is extremely simple.
+
+### What kind of things can I log to?
+Anything that is a file descriptor and can be written to with write() and fsync(). This includes the following:
+- pipes
+- files
+- stdout
+- stderr
+- sockets (untested)
+
+### How do I use this library?
+- [See the API](alog.h)
+- [See the tests](tests/log_test.c)
 
 # How to build
 ```bash
 $ make so
 ```
 
+# How to test
+```
+
 # Variables
 The following (shell) variables can be set to influence behavior at runtime: