Add missing EPL-1.0 LICENSE file

One requirement for licensing code under the EPL is that "a copy of this Agreement [the EPL] must be included with each copy of the Program." [0]. Unfortunately clojuredocs-client does not comply with this requirement even though its README.md claims that it is licensed under the EPL.

Additionally it would be nice if *every* source file could mention its license explicitly. That is it should include a statement of copyright and, for the EPL, a header such as:
 ```
THE ACCOMPANYING PROGRAM IS PROVIDED UNDER THE TERMS OF THIS ECLIPSE PUBLIC
LICENSE ("AGREEMENT"). ANY USE, REPRODUCTION OR DISTRIBUTION OF THE PROGRAM
CONSTITUTES RECIPIENT'S ACCEPTANCE OF THIS AGREEMENT.
```

Please kindly accept this pull request and release a new version of clojuredocs-client as it is not legally distributable in its current form.

[0] http://www.eclipse.org/legal/epl-v10.html → 3. REQUIREMENTS