graphlog: split the actual DAG grapher out into a separate method
This allows extensions like pbranch to use asciigraph() to graph dependencies
for patch branches, but could be used for basically any DAG.
0: Adding root node
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0: Adding root node
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marked working directory as branch a
1: Adding a branch
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1: Adding a branch
=======
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
marked working directory as branch b
created new head
2: Adding b branch
1: Adding a branch
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2: Adding b branch
=======
3: Adding b branch head 1
1: Adding a branch
-------
3: Adding b branch head 1
=======
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
created new head
4: Adding b branch head 2
3: Adding b branch head 1
1: Adding a branch
-------
4: Adding b branch head 2
3: Adding b branch head 1
=======
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
created new head
5: Adding b branch head 3
4: Adding b branch head 2
3: Adding b branch head 1
1: Adding a branch
-------
5: Adding b branch head 3
4: Adding b branch head 2
3: Adding b branch head 1
=======
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
6: Merging b branch head 2 and b branch head 3
3: Adding b branch head 1
1: Adding a branch
-------
6: Merging b branch head 2 and b branch head 3
3: Adding b branch head 1
=======
marked working directory as branch c
7: Adding c branch
3: Adding b branch head 1
1: Adding a branch
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7: Adding c branch
=======
no changes on branch c containing . are reachable from 3
1
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7: Adding c branch
0
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0 files updated, 0 files merged, 2 files removed, 0 files unresolved
0
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3: Adding b branch head 1
0
-------
3: Adding b branch head 1
6: Merging b branch head 2 and b branch head 3
0
-------
no changes on branch b containing . are reachable from 7
1
=======
0 files updated, 0 files merged, 2 files removed, 0 files unresolved
7: Adding c branch
3: Adding b branch head 1
1: Adding a branch
-------
0: Adding root node
-------
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
7: Adding c branch
3: Adding b branch head 1
1: Adding a branch
-------
1: Adding a branch
-------
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
7: Adding c branch
3: Adding b branch head 1
1: Adding a branch
-------
6: Merging b branch head 2 and b branch head 3
3: Adding b branch head 1
-------
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
7: Adding c branch
3: Adding b branch head 1
1: Adding a branch
-------
6: Merging b branch head 2 and b branch head 3
3: Adding b branch head 1
-------
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
7: Adding c branch
3: Adding b branch head 1
1: Adding a branch
-------
6: Merging b branch head 2 and b branch head 3
3: Adding b branch head 1
-------
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
7: Adding c branch
3: Adding b branch head 1
1: Adding a branch
-------
6: Merging b branch head 2 and b branch head 3
3: Adding b branch head 1
-------
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
7: Adding c branch
3: Adding b branch head 1
1: Adding a branch
-------
6: Merging b branch head 2 and b branch head 3
3: Adding b branch head 1
-------
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
7: Adding c branch
3: Adding b branch head 1
1: Adding a branch
-------
7: Adding c branch
-------
=======
1: Adding a branch
-------
6: Merging b branch head 2 and b branch head 3
3: Adding b branch head 1
-------
7: Adding c branch
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abort: unknown revision 'z'!
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=======
0: Adding root node
1: Adding a branch
6: Merging b branch head 2 and b branch head 3
3: Adding b branch head 1
7: Adding c branch