#192 Allow to move section during merge

[Sir Zooro]

I am performing 3-way merge of multiple files. Sometimes I have situation like this:

Common code
Conflict: B1, C1
B2
Common code

Correct merge should look this way:

Common code
B1
B2
C1
Common code

Another example: these conflicts:
Common code
Conflict: B1, C1
Optionally some common part, e.g. empty line
Conflict: B2, C2
Common code

should be resolved this way:

Common code
B1
B2
C1
C2
Common code

Now I have to manually copy and paste pieces of code. Please add new command to move one of conflicts to next merge section. You can also add some "code snippet" handling. Please do not use system clipboard for this - I need it to hold another piece of code.

[Sir Zooro]

Update: I found that with block merging and splitting I can merge many such cases without copying/pasting code. However there is still one case which cannot be handled this way, and this function would be handy. It usually looks this way:

[contributor 1]
[tab]if (x > 0)

[contributor 2]
[4spaces]if (x > 0)

[contributor 3]
some_new_code();
[4spaces]if (x > 0 && y > 0)

BTW, this should be feature request instead of bug. Please change this if you can.