add missing includes to common.h
dispatch_request belongs to daemon, move it there
factor out xmlrpc rpc related functions
Output of --help and --version have to go to stdout

To allow 'flowgrind -h | less' --help's and --version's output have to
go to stdout and not to stderr.
Merge branch 'next' into rpccleanup
include config.h first
Merge branch 'next' of github.com:flowgrind/flowgrind into help-to-stdout
Merge pull request #170 from alexander-zimmermann/next

flowgrind: properly fix compiler warning
Merge pull request #166 from arnd/rpccleanup

Rpccleanup
Merge pull request #168 from alexander-zimmermann/help-to-stdout

Output of --help and --version have to go to stdout