optimization to flag basic / implementation of a custom rolling wrapper

See merge request !103

Bump matplotlib from 3.3.1 to 3.3.2

See merge request !102

Delay expansion of regular expressions

See merge request !101

function, as dynamically assigned variables are missing otherwise

bugfix: unmasking reinjected the new (i.e. nan) instead of the old values (this should have been caught by a test)

Bump numpy from 1.19.1 to 1.19.2

See merge request !98

Bumps [numpy](https://github.com/numpy/numpy) from 1.19.1 to 1.19.2.
- [Release notes](https://github.com/numpy/numpy/releases)
- [Changelog](https://github.com/numpy/numpy/blob/master/doc/HOWTO_RELEASE.rst.txt)
- [Commits](https://github.com/numpy/numpy/compare/v1.19.1...v1.19.2)

Bump pandas from 1.1.1 to 1.1.2

See merge request !97

Bumps [pandas](https://github.com/pandas-dev/pandas) from 1.1.1 to 1.1.2.
- [Release notes](https://github.com/pandas-dev/pandas/releases)
- [Changelog](https://github.com/pandas-dev/pandas/blob/master/RELEASE.md)
- [Commits](https://github.com/pandas-dev/pandas/compare/v1.1.1...v1.1.2)

Bump attrs from 20.1.0 to 20.2.0

See merge request !95

Bump numba from 0.51.1 to 0.51.2

See merge request !94

        failed, as they were evaluated during 'compile' time instead
        of execution time