Added a Makefile that matches gittip/www.gittip.com's, where appropriate.
Add `make minify` and `make all`.
Make everything except `make clean` rely on node_modules.
Remove unnecessary line from Makefile.
Merge pull request #42 from gittip/gittip-compatible-makefile

Added a Makefile that matches gittip/www.gittip.com's, where appropriate.