Make Bazel itself build under an output base with Unicode characters

[fmeum]

• All decompression functions used in repository rules are modified to go through Path#getInputStream(), thus avoiding string encoding issues when constructing a FileInputStream manually.
• A new Path#createTempDirectory function is introduced to replace error-prone usages of Files.createTempDirectory throughout the code base, which requires reencoding of both the arguments and the return value.
• Fix encoding of argv0 in SubprocessBuilder and WorkerMultiplexer.
• Fix encoding of the path of and the content in the server log file.
• Fix encoding of info output.

Work towards #374
Fixes #24444

[fmeum]

I suspect that the RBE failure is due to the remote execution environment not having the C.UTF-8 locale installed which is forced for Java compilation actions. Would it be possible to add it?

[tjgq]

I suspect that the RBE failure is due to the remote execution environment not having the C.UTF-8 locale installed which is forced for Java compilation actions. Would it be possible to add it?

I think that entails creating a new docker image for RBE (or finding a suitable existing one). @coeuvre, do you know how to do this?

If this is blocking for 8.0.0, I suggest finding a way to either detect the existence of the locale in the test, or disable it when on RBE.

[fmeum]

The test is failing on other platforms, so I'll look into that. It's not a hard blocker for 8.0.0, it can equally well go into 8.1.0.

[fmeum]

This needs a fix in rules_java to properly set a UTF-8 environment for bootstrap actions: bazelbuild/rules_java#243