- Make variable name more semantic
- Reduce cyclomatic complexities for the formula calculate function
- Support specified unzip size limit on open file options, avoid zip bombs vulnerability attack
- Typo fix for documentation and error message

According to issue #409

There is absolutely no reason for the timezone to be in UTC, and converting the local times to UTC while keeping values is hacky at least.

Excel has no understanding of timezones, hence the user of this library should know what timezone their values are supposed to be, by following the timezone within their timeTime structs.

This closes #652, new SetColWidth API, support set column width in stream writing mode, and export error message

Signed-off-by: NVaibhav Nayak <vaibhav.nayak@gmail.com>

Exported functions:

SetCellStyle
InsertCol
RemoveCol
RemoveRow
InsertRow
DuplicateRow
DuplicateRowTo
SetRowHeight
GetRowHeight
GetCellValue
GetCellFormula
GetCellHyperLink
SetCellHyperLink
SetCellInt
SetCellBool
SetCellFloat
SetCellStr
SetCellDefault
GetCellStyle
SetCellValue
MergeCell
SetSheetRow
SetRowVisible
GetRowVisible
SetRowOutlineLevel
GetRowOutlineLevel
GetRows
Columns
SearchSheet
AddTable
GetPicture
AutoFilter
GetColVisible
SetColVisible
GetColOutlineLevel
SetColOutlineLevel
SetColWidth
GetColWidth

inner functions:

adjustHelper
adjustMergeCells
adjustAutoFilter
prepareCell
setDefaultTimeStyle
timeToExcelTime
addDrawingChart
addDrawingVML
addDrawingPicture
getTotalRowsCols
checkRow
addDrawingShape
addTable

* Huge refactorig for consistent col/row numbering

Started from simply changing ToALphaString()/TitleToNumber() logic and related fixes.
But have to go deeper, do fixes, after do related fixes and again and again.

Major improvements:

1. Tests made stronger again (But still be weak).
2. "Empty" returns for incorrect input replaces with panic.
3. Check for correct col/row/cell naming & addressing by default.
4. Removed huge amount of duplicated code.
5. Removed ToALphaString(), TitleToNumber() and it helpers functions at all,
and replaced with SplitCellName(), JoinCellName(), ColumnNameToNumber(), ColumnNumberToName(), CellNameToCoordinates(), CoordinatesToCellName().
6. Minor fixes for internal variable naming for code readability (ex. col, row for input params, colIdx, rowIdx for slice indexes etc).

* Formatting fixes

Primary motivation: Avoid statefull tests with not ignorable git file tree changes.
Multiple tests reads and overwrites signle file for won needs.
Multiple tests reads and overwrites file under version control.

Secondary motivation: Minimal tests logic aligment, separate error expectation
and not error expectation tests. Introduce sub-test over test data sets and so far.

This commit is not ideal but necessary (IMHO)

Golangs time.Duration uses nanoseconds, thus it is limited to approximately 290 years.