Replace less plugin

[Deraen]

In my very biased opinion less4clj would be better choice than lein-less.

Pros:

• Uses native Java less compiler instead of very old Less.js (1.7.2 instead of 2.7.3)
  • new Less.js doesn't support Nashorn so updating lein-less is very hard
  • Latest less4j has feature parity with less.js 2.6.0 features
• Uses recent Less version
• Allows importing files directly from classpath (e.g. webjars and cljsjs packages)

I can implement this if others agree this is good idea.

[yogthos]

That sounds reasonable to me, would you be up for doing a pr?