* Fixed issue #539 Fixed error opening excel file created in encoding different from UTF-8, added logging of possible errors when decoding XML if the function does not provide exit with an error

* Added test for CharsetReader

* Fixed #discussion_r359397878

Discussion: https://github.com/360EntSecGroup-Skylar/excelize/pull/540#discussion_r359397878

* Fixed go fmt

* go mod tidy and removed unused imports

* The code has been refactored

Add missing ShowZeros SheetViewOption implementation

* Allow access to more formula attributes in SetCellFormula

Make SetCellFormula variadic to not break API.
The new arguments are option arguments in which the type of
the formula and the ref attribute may be set.
These need to be set for an array formula to work.

* Add TestWriteArrayFormula to test optional parameters of SetCellFormula

TestWriteArrayFormula writes a document to the test directory that
contains array formulas that are used to calculate standard deviations.
The file also contains values calculated by the Go testcase, so the
results can be verified. It should be tested, if the array formula
works (i.e. shows a number, not an error) and that the values calculated
by the formula and those calculated by Go are the same.

workBookRelsWriter, drawingRelsWriter into relsWriter;
drawingRelsReader, workbookRelsReader, workSheetRelsReader into relsReader;
addDrawingRelationships, addSheetRelationships into addRels

Fix dependency on github.com/360EntSecGroup-Skylar/excelize v1

* #386 regression test added

* closes #386 string to bigint on GOARCH=386

Updating Readme

Removing the /v2 on the package url as it does not work with the ```go get``` command.

add missing error check in SetSheetRow()

SetCellValue: use fmt.Sprint(v) instead of fmt.Sprintf("%v", v)

Because that does the same thing, but without having to parse a format
string.
Signed-off-by: NOlivier Mengué <dolmen@cpan.org>

Fixed #462 Handle multi row inline strings

Fix potential memory leak

The inline string struct is actually the same
as the shared strings struct, reuse it.

Note that Go version 1.10 is required.

Fixes #462

Get sheet names based on index

Fix potential memory leak where zw is not Close() when an error occurs.

SheetID only seems to indicate the file name for the sheet.
Check the sheets list based on index instead. Reordering sheets
in Excel changes the order they appear in that list.

Fixes #457

Further improve read performance

Instead of re-encoding the full sheet to change the namespaces
in the encoded bytes, read the sheet again and do the byte
replacements there.

In this case, file access ends up being more performant than
marshaling the sheet back to XML.

In the SharedStrings test, ensure the strings are actually read.

Fix #439

Update comments

Bugfix #454

Fix #439 

We were parsing the whole sheet twice since the
sheet reader already reads in all the rows.

getTotalRowsCols function is unused after these changes
so it has been deleted as well.

Closes #439