Wrap prerequisite package installation commands

The new GitHub layout appears to limit the line length of code blocks
to 80 characters.

Signed-off-by: Jussi Virtanen <jussi.k.virtanen@gmail.com>
Add 'libevent' to prerequisite packages

Signed-off-by: Jussi Virtanen <jussi.k.virtanen@gmail.com>
Fix Debian build

Link 'fast_client' against 'libm'.

Signed-off-by: Jussi Virtanen <jussi.k.virtanen@gmail.com>
Merge pull request #56 from jvirtanen/fixes/documentation

Add 'libevent' to prerequisite packages
Merge pull request #57 from jvirtanen/fixes/debian

Fix Debian build