Travis-CI Skeleton Project for DMD 2.064.2 and LDC 0.12.1

[Dylan Knutson]

Hello,

I was hoping for Travis-CI to provide a set of D compilers for 
building projects written in D, but alas, they do not.

So, here's a small skeleton project that I'm using for testing my 
D projects with DMD 2.064.2 and LDC 0.12.1.

It should be straightforward to bring in the relevant parts of 
the .travis.yml and Makefile into another project; just copy over 
the .travis_scripts folder, the install and env portions of the 
config in .travis.yml and it should be good to go.