Integration of Documentation facilities into the Juno IDE

Juno as an IDE (and, since the introduction of JuliaPro, the quasi-standard IDE for Julia) has matured quite a bit during the last years, but the integration of documentation facilities is still somewhat lacking. In particular, there is no way to search for docstrings and displaying them is limited to the console and inline documentation. This proposal aims at implementing documentation search for local packages and improving their display in Juno.