Make inline functions static (fixes #1).

When not declared static, on -O0 gcc will generate external linkage.
Merge branch 'master' of github.com:cengizIO/lstack
Revert "Update Makefile for using with Eclipse CDT; Fix -O0 undefined reference for inline function"

This reverts commit 5405f76e0bb6b9cc40164f7d710e7f2c5530fc2e.