ci: Make travis-ci to run all test cases

Change-Id: I78fa6fcdfbe3eda5b7c1fe5c063be9549d8185a7
rib: Making single configuration file for both nrd and nfd

Change-Id: I4f03896459e8dc8564c44a7b610cd1351473d966
Refs: #1486, #1412
docs: Adding installation instructions and configuration tips

README.md and INSTALL.md now redirect to documentation in docs/ folder.
Later we will add links to HTML pages with NFD documentation.

Change-Id: I4f02f3166e7802570b24ed225ac4de8c56c6e64e
Refs: #1446
rib: Switching to use global IO

Change-Id: I5eca302c65d868810bd59ab654b7ea74762dc7ee