moved range expression code to its own module

Because circular imports are coming near
catch range syntax error
synctool-config supports range syntax
don't mention the obvious

read the manual
fits on one line
node range expressions in synctool.conf file
updated example config with range syntax
catch RangeSyntaxError
ignore_group also supports range syntax
config slave supports range syntax
only moved code
config compound group with range syntax
default_nodeset accepts range syntax
Merge branch 'range'
support node range syntax on the command-line
support node range syntax in config file (in many places)
ignore ridiculously large ranges

or patch the code if your cluster is really that large
display "the first" unknown node in range