first version of Makefile for compiling tincd from source
change git protocol from git:// to http://
fixed a bug in clean rule of Makefile and fixed script bug in clean rule
add rule install to Makefile
add some more debug output
intruduce basic logging feature - correct order of tinc compilation
extend logging feature and checksum computation
add support for prerequisite check for required programs
use var ANDROID_NDK for installed or user provided NDK
output version of tinc
Merge luckyhacky's PR to automate build of tincd binary for ARM.

Reviewed makefile to have better dependency tree and avoid many if/else
blocks.
Use latest OpenSSL and disable PIE to avoid re-occurrence of issue #9.

This should close #7.