Documentation: merge: move merge strategy list to end

So the section layout changes as follows: NAME SYNOPSIS DESCRIPTION OPTIONS -MERGE STRATEGIES HOW MERGE WORKS HOW CONFLICTS ARE PRESENTED HOW TO RESOLVE CONFLICTS EXAMPLES +MERGE STRATEGIES CONFIGURATION SEE ALSO AUTHOR DOCUMENTATION GIT NOTES The first-time user will care more about conflicts than about strategies other than 'recursive'. One of the examples uses -s ours, but I do not think this hinders readability. Suggested-by: Thomas Rast <trast@student.ethz.ch> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Thomas Rast <trast@student.ethz.ch>