TCPL: Chapter 1.7 - Functions

Signed-off-by: Ino Gamalinda <ino.gamalinda@teamcodeflux.com>
TCPL: Exercise 1.15 - Rewrite temperature conversion but use functions

Rewrite of chapter-1.2.c

Signed-off-by: Ino Gamalinda <ino.gamalinda@teamcodeflux.com>
Merge branch 'exercise-1-15' into chapter-1.7
Merge branch 'chapter-1.7' into chapter-1