Update Makefile

Add OPTFLAGS as we RPM wants to build with %{optflags}.
Merge pull request #9 from cicku/patch-1

Support OPTFLAGS in Makefile
Add license headers
Version 0.5
Increase maximum line length
Filter out irrelevant mapping notify events
Version 0.5.1
Use compliant header guard
Decrease the header guards collision chances
Generate header function prototypes from .c
Improve const-correctness
Log all mapping notify events
Version 0.5.2