Try to use powershell to strip path information before it pollutes the output file

When building the list of Javascript files to append, we currently stick the file's full name (including path) into the output file.

This change uses powershell to remove the absolute path information. This is beneficial for two reasons:

1. We should not be leaking path information into the compiled output. In particular, paths may contain usernames which could be considered sensitive information.
2. Paths on non-English systems may contain characters outside of ASCII, which cause problems (see #2220 (closed), for instance)

If powershell is not present or not functional on the user's system, the build script will simply continue doing what it does now. It's a standard windows component now (in Windows 8 and later at least), so that should be rare.

Note that this MR also temporarily changes the active codepage to 65001 to allow paths with arbitrary characters. Codepage 65001 is known to be broken on Windows Vista and earlier; I assume we don't care.

added 1 commit

• 3212ece7 - casing for consistency

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merged

mentioned in commit 701a9135

mentioned in issue #2222 (closed)

mentioned in commit 1d2ba32e

mentioned in merge request !7656 (merged)

mentioned in merge request !7657 (merged)