Add a bootstrapping script and a sample configuration

Add a bootstrapping script and a sample configuration

This adds a script that installs necessary build dependencies to the
system, builds and installs collectd into an 'install/' subdirectory,
installs a sample config and starts collectd in foreground mode
afterwards.

Note that this script is entirely optional but it may help you to get
started (some plugins don't compile, so this script is only building a
few). Once installed this way, another 'make install' will re-install
collectd into install/sbin/collectd and it can be started normally.

NOTE: collectd segfaults in src/daemon/metric.c:208 (called from
src/cpu.c:545) when build this way from the current branch HEAD. It
works on tree 630b948, so it's likely caused by your code and you
already got something to fix. :-)

ChangeLog: collectd: added bootstrap helper script