Check for null when loading print titles. Ignore if range not found.

Merge pull request #306 from TDaphneB/patch-1 ...

Register hyperlink with 2 params in CalcEngine

Fix column width in reference file

Merge pull request #284 from clinchergt/image-support ...

Add image support

Add files via upload

Update hyperlinks Excel file used for tests

Updated example hyperlink file

Add special case for indexed color 81 - return black. Fixes #307

Allow omitted parameters. Fixes #303

Add tests for XLPicture and XLMarker classes ...

Tests mostly methods that aren't just direct setters and getters using the
known values of the resource image.

Code cleanup to comply with project standards ...

Also, renamed a few tests and files

Merge pull request #295 from igitur/issue293-allow-access-to-cell-stored-value ...

Check OADate range before parsing. Return string if parsing fails.

Add support for other image formats ...

The format should be set on the Type property of the XLPicture object, it
should be set as a string, the class will then try to convert it to a valid
format. If it fails to do so, it will set the format to Jpeg.

Make drawing and blip IDs consistent

Add image handling tests

Check OADate range before parsing. Return string if parsing fails.

Upgrade OpenXML to v2.7.1

Upgrade to .NET 4.5.2

Merge branch 'develop' of https://github.com/closedxml/closedxml into issue252-evaluate-formulas-when-saving

Revert "Force failed test to test appveyor compiler directive" ...

This reverts commit 7d8490f.

Force failed test to test appveyor compiler directive

Add support for AppVeyor command line environment variable.

Don't execute OleDb tests on appveyor - add preprocessor directive

Add tests to evaluate file through OleDb

Update reference file after allowing 8:9 range.

Add option to evaluate formula when saving workbook. Fixes #252

Change normal Formulas unit test to check for equality of 2 cells that should be equal

Support references with Sheet1!A1:Sheet1!A50 style reference (sheet names)

Allow row ranges e.g. 1:5

Parse commas in print area (#263) ...

* add method to format the defined names if a comma exists in the sheet name

* add Excel workbook to test loading of sheets with commas in them (when they have a print area)

* Regex change to make sure all tests pass successfully

* use String.Format instead of new fangled string interpolation.

* Improve defined name parsing.

* Add unit test for references to a sheet with commas in the name

* Add unit tests and adjust CalcEngine to allow enclosing characters around identifiers

* Reformat code using CodeMaid

* Don't use C#6 syntax for dictionary initialiser.