Add support for nmcli v0.9.10 command interface

nmcli v0.9.10 has some backward incompatible changes in its command
names. A list of the differences from v0.9.8 can be found at
https://wiki.gnome.org/Projects/NetworkManager/nmcli
Fix parsing of blank lines in nmcli output
Escape backslash in docstring
Add network.connection_name option

I have a “DHCP” and a “Wired Shared” connection in network manager which
are both wired. For some reason, nmcli would give me “Wired Shared” as
the first one, restarting that one. That broke the restarting feature
for me, so I added this new option that lets me fix the name to “DHCP”
without removing the other one from network manager.
Changelog entry
Add a Travis CI file
Add Travis CI Image to the README
Add some requirements
Print out Python version in setup.py
Upgrade Python version
Do not use python3 but just call python
Warn about incompleteness of `make install`, #76

Currently, `make install` is not sufficient to get everything working.
Since there are subtle differences between the distributions, the `make
install` does not do everything itself but rather just do the
independent parts. For the full installation, the `make full-install`
with `./setup.py install` was needed.

Now I have ample warnings for each case and included `./setup.py
install` into the `make full-install` which all link to the
documentation.
Fix hiding of Unity launcher (Fixes #72)
Changelog entry