The following changes take effect:
1. Annotate FixedStringBuffer => `FixedStringBuffer` in many places.
2. Remove non-existing helpers for FixedStringBuffers. I added them
previously but even then they were removed in a following fixup so these
references were never valid. Therefore let's just put a vague reference
to the fact that we have some helpers for this class in the Kernel, and
let people to figure out quickly by themselves for this topic.
3. Put a sentence to explain that FixedStringBuffer objects are not only
being used in syscall handling code, but also for storing actual data in
both the Thread and Process classes as well.
This filesystem is based on the code of the long-lived TmpFS. It differs
from that filesystem in one keypoint - its root inode doesn't have a
sticky bit on it.
Therefore, we mount it on /dev, to ensure only root can modify files on
that directory. In addition to that, /tmp is mounted directly in the
SystemServer main (start) code, so it's no longer specified in the fstab
file. We ensure that /tmp has a sticky bit and has the value 0777 for
root directory permissions, which is certainly a special case when using
RAM-backed (and in general other) filesystems.
Because of these 2 changes, it's no longer needed to maintain the TmpFS
filesystem, hence it's removed (renamed to RAMFS), because the RAMFS
represents the purpose of this filesystem in a much better way - it
relies on being backed by RAM "storage", and therefore it's easy to
conclude it's temporary and volatile, so its content is gone on either
system shutdown or unmounting of the filesystem.
The default template argument is only used in one place, and it
looks like it was probably just an oversight. The rest of the Kernel
code all uses u8 as the type. So lets make that the default and remove
the unused template argument, as there doesn't seem to be a reason to
allow the size to be customizable.
