(svn.branchmerge.using.create): Use '^' notation in branch creation
command line example.
(svn.branchmerge.using.work): Use a slightly more complicated branching
example that follows along with a sample repository I'm creating for
this chapter. Point to the new png diagram below.
* en/book/images/basic-branch.odg: New source file for the revised png
below. Note that I couldn't find the FreeSans font for Windows, so I
used Arial. I'll need to edit this and any additional diagrams I revise
later on a linux box (which I'm assuming I can find FreeSans for).
* en/book/images/ch04dia4.png: Deleted and replaced with...
* en/book/images/basic-branch.png: ...this.
