grep: display correct user/revision for --all in reverse.
Also handle multiple occurrences of the same line by storing
linestates in an array instead of a dict, and using difflib
to compute the difference between linestates.
[('bool1', 'true'), ('bool2', 'false'), ('string', 'string value')]
[('list1', 'foo'), ('list2', 'foo bar baz'), ('list3', 'alice, bob'), ('list4', 'foo bar baz alice, bob')]
---
'string value'
'true'
'false'
None
---
Not a boolean: string value
True
False
False
False
True
---
['foo']
['foo', 'bar', 'baz']
['alice', 'bob']
['foo', 'bar', 'baz', 'alice', 'bob']
['foo', 'bar', 'baz', 'alice', 'bob']
[]
[]
['foo']
['foo']
['foo', 'bar']
['foo', 'bar']
['foo bar']
['foo', 'bar']
---