Some programs (which?) might create temporary files like `~name` or
`_name`, but maybe there are people who actually rely on names like
`_name`. Let's restrict the filter to just dotfiles for now.

I was a bit surprised to get an "UnicodeDecodeError: 'utf-8' codec can't
decode byte 0xbe in position 21: invalid start byte" error while
writing and testing a new magic file.

It turns out that binwalk tried to parse the Vim swap file (.magic.swp)
as a magic file which obviously fails. Therefore ignore all files not
starting with an alphanumeric character.

Improved support for DIR100D1/E1 firmware files

deps.sh: replace a leftover "sudo" with "$SUDO"

Added comment to extract.conf noting the use of an internal plugin for Hilink encrypted firmware extraction.

Fixed extraction bugs when recursively extracting multiple files at once; added some extraction API methods.

deps: check for package installation failure

Improve (U)EFI structures detection

GUIDs coming from https://github.com/LongSoft/UEFITool/blob/new_engine/common/ffs.h

Invalidate capsules with unrealistic sizes, but would be better to check
against the remaining data length.

This should avoid reporting a number of false positives on UEFI PI headers,
and includes a list of known filesystems based on
https://github.com/LongSoft/UEFITool/blob/new_engine/common/ffs.h

The _FVH header is the actual fixed header, the GUID identifies the type of
filesystem instead. Since this seems to be the only known GUID valid for
this structure, accept it by itself, and report the size of the volume and
header.

Identify the GUIDs for EFI Capsule formats, both v0.9, v2 and UEFI
versions, which are essentially the same for what gets reported.