Release 1.7.57 of scc-win

This release uses a new production mechanism (Wix toolset) and MSI installer.
To upgrade from 1.6 (and earlier) versions, first uninstall the actual version of
SCC for Windows and then install the new version. Scheduling is compatible with
previous releases.

The release contains an updated blat.exe and minor changes for collected scheduled
tasks data to avoid unimportant changes in the logbook.

Refer to the release notes for the detailed release notes.