Convert less to use bootstrap variables and mixins

[Julusian]

The changes look like more than there is, as a different version of less appears to be in use.

[nakupanda]

Hi,

Just tried your changes and found font was small than before, will give you more feedback later.

Thanks for you contribution!

[Julusian]

It looks like something weird is going on with the css/less i forked from.
It appears that your css files arent compiled from the current version of the less.
I have created another pull request to fix this.
#137

[nakupanda]

You're right, the less file was created by other contributor based on the css file that had been written, I think during the process something was missing.

[fabn]

Could this be rebased to use latest version? It would be very useful to use less file as is instead of copying and pasting it only to add default bootstrap variables.

[Julusian]

I've just pushed a rebased version

[nakupanda]

Merged into master, thank you.

If possible, I would suggest exporting .less file to /dist/less directory too.