Added comment reading testdata

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branch : 1.8
extra : rebase_source : 59cdb71bd721d1c7be78db7cacf4fafa955e84af
Added function to determine location of comment files based on contents of rels files

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branch : 1.8
extra : rebase_source : 37e50387334c86a093e6327d8b068d9490b4c2f9
Added function to read comments from an XML string

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branch : 1.8
extra : rebase_source : 0eb524dd7c1536624f107008a98b2e9711c1b473
Some cleanup

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branch : 1.8
extra : rebase_source : 688d936a069438b7d51f97c57a7e51bea6410254
Completely forgot to test

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branch : 1.8
extra : rebase_source : d3226af03b082217add182d1bded7b6eff6e5487
Comments are now read and assigned to their cells. Basic unit test also included (and passes)

--HG--
branch : 1.8
extra : rebase_source : fcc9171b8d2705a5644635229c5e93d4d57d7e08
reverted mistaken change

--HG--
branch : 1.8
extra : rebase_source : b0c195f82828b85bb3050ff86d00dcb08493813b
Fixed other mistaken changes

--HG--
branch : 1.8
extra : rebase_source : 5a3e15b1d7183ad9dedc5730a7b0c3c69ffb0fef
Better unit tests

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branch : 1.8
extra : rebase_source : 4bf0f3a0b9b40ad96d02f402fd824bccb37ea120
Added self to authors file

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branch : 1.8
extra : rebase_source : 3a9dacd9529ce01029d765be39260f1639f66476
Added documentation

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branch : 1.8
extra : rebase_source : 58ea6178340b7f221843acde18e823c5230da118
Added slots to comment class

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branch : 1.8
Removed bad unit tests

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branch : 1.8
Made Comment a new-style class

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branch : 1.8
Added tests for comment class

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branch : 1.8
Full unit tests

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branch : 1.8
Made use of properties and added docs

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branch : 1.8
Removed line of debugging output

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branch : 1.8
Fixed a typo in docs. openpyxl not pyopenxl.

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branch : 1.8
Comment snow have a reference to their parent cell rather than a coordinate

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branch : 1.8