wix: more robust normalization of RC version components MSI has strict version requirements where the format is `A.B.C[.D]` and all fields must be numeric (https://docs.microsoft.com/en-us/windows/win32/msi/productversion?redirectedfrom=MSDN). Only the first 3 are used by the installer itself. Mercurial's version strings can have `rcN` and an optional `+<commit>-<date>` fragment at the end. This commit teaches the MSI version normalization to handle both of these more robustly. Before, we would throw away the `.rcN` component completely. e.g. `5.3rc1` would get normalized to `5.3.0`. And worse, `5.3rc0+5-abcdef` would get normalized to `5.3.5`. After this commit, presence of an `.rcN` provides the value for a 4th field. e.g. `5.3rc1` -> `5.3.0.1`. In addition, the commit count from the `+` suffix gets normalized into the 4th version component, but only if the original version string didn't have a 4th version component or if no `rcN` is present. e.g. `5.3+5-abcdef` is `5.3.0.5`. Differential Revision: https://phab.mercurial-scm.org/D8003