* optimize marshal

* optimize mem alloc

* add benchmark testing

* add NewSheetWithRowNum testing

* sync struct fields order

* add BenchmarkNewSheetWithStreamWriter

* delete NewSheetWithRowNum and benchmark test

This closes #714 and closes #715, fix wrong worksheet index returned by NewSheet in some case, fix panic on formatted value with no built-in number format ID

- Update unit test

Default row height compatibility with Apache OpenOffice and Kingsoft WPS, unit test update and typo fixed

- typo fix, resolve #635

-  added 3 internal function: getSheetID, getActiveSheetID, getSheetNameByID

Resolve #580, revert commit https://github.com/360EntSecGroup-Skylar/excelize/commit/5ca7231ed408ac264f509ff52b5d28ff4fbda757

* 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

Fix #494

If a row is full, don't bother allocating a new one, just return it.

Use the last populated row as a hint for the size of new rows.

Simplify checkSheet to remove row map

* Added accessors for Getting/Setting Page Margins

* Added test cases