improve hashmap api, now thread-safe

README.md

@@ -1,9 +1,10 @@
 # myclib
 
-This is a personal C library created for learning and experimentation.  
+**myclib** is a personal C library. This project is a work in progress and intended for educational use.  
 It is not production-ready. Use at your own risk.
 
 ## Features
 
-- Hashmaps
-- Dynamic strings (requires linking with the math library)
+- Hashmaps - Thread-safe (MT Safe)
+- Dynamic strings - Not thread-safe (MT Unsafe)
+  > Requires linking with the C math library (`-lm`)