``desing/blowup2``

Performing blowing up operation on a chart-record along a given
center. The center is defined either by giving indices to
`IND` or by giving the defining equations of normal crossing
hypersurfaces. The procedure creates new chart-records whose charts
cover the blown up variety and the basic objects are transformed
properly along the stack. The new charts are embedded into the affine
ambient space of the input chart (i.e. the number of *k*-algebra
generators remain the same).

**Input:**-
**O**- a chart-record,
**C**- a list of pairwise different indices to the
`IND`
member of the chart of the chart-record or the generators of
normal crossing hypersurfaces defining the blowing up center,
**gp**- boolean, true if the transformation is a "goodpoint"
blowing up, false in the generic case.

**Output:**- a list of chart-records covering the blowing up of the
input chart along the canter
*C*, such that all charts has ambient
affine space with the same dimension as the input chart.

The input chart is moved to **chartHistory** and the operation is
registered in **chartTree**. The value of
**globalChartCounter** is increased as needed.
This variant of blowup is used when **skewcover** is true.