mlaunch tests: do not require arbiter be last in the replset.
test_mlaunch: test large (12 node) replsets.

With and without arbiters.

Currently fails, because all nodes have the default votes: 1.
mlaunch: Allow over 7 nodes.

All nodes over the 7th (or 6th if --arbiter) get votes: 0.

Fixes #123.
Merge pull request #125 from devkev/feature-arbtest

mlaunch tests: do not require arbiter be last in the replset.
renamed "other" group label for --group-limit to "all others combined" to be more specific.
added new parameter --stacked to histogram plots to switch between stacked/nonstacked bar histograms.
pattern extraction from loglines. can be used to group by "pattern" in mplotqueries.
added tests for pattern extraction. Fixes #129.
Merge branch 'develop' of github.com:rueckstiess/mtools into feature-129-pattern
Merge branch 'develop' of github.com:rueckstiess/mtools into develop
Merge branch 'feature-129-pattern' into develop
Merge branch 'feature-123-novotes' of github.com:devkev/mtools into devkev-feature-123-novotes
added mplotqueries option --xpos start. This will plot the start times of ops with duration, rather than when they ended (and were logged).
updated CHANGES to reflect changes so far for 1.1.1.
added durline plot (--type durline).
small cosmetic fix.
renamed parameter --xpos start  to  --optime-start
mention durline plot in changes. add work-around for windows to not use SIGPIPE.
bumped version to 1.1.2dev
fixed edge case where parsing loglines could break when they don't have datetime but do have duration.
made mlogvis much faster by checking logline parsing first for duration, then for datetime. Fixes #134.