Bug#897304: O: pmount -- mount removable devices as normal user

[Antonin Décimo <antonin.decimo@gmail.com>]

Hello pmount users,

I have the intent of taking care of upstream pmount.
My code can be found here:

    https://github.com/MisterDA/pmount

I have spend the last few days gathering patches from around. I’ve
found:
- the Debian Bug report logs;
- patches in distros from Debian and Arch Linux;
- two repositories.
I’ve integrated the patches as well as I could, while respecting the
authors, contributors, and the date of the patch.

Then, I’ve spun up my compilers and static analyzers and overhauled
the pmount code. I haven't changed much of the user interface; I’ve
mostly made internal rewrites. Here is a condensed ChangeLog to this
day:

The user-visible changes include:
- support btrfs, nilfs2, f2fs, exfat (via fuse), ntfs.
- fix Bash completion
- add --utc option
- support tz=UTC
- add --selinux-context option to specify a SELinux context
- remove pmount-hal, as HAL is deprecated
- fix UTF-8 detection
- switch from Autotools to Meson+Ninja build system

Internally, some notable changes include:
- switch from the realpath(3) custom implementation to libc
- remove occurrences of PATH_MAX to favor allocations on heap and
  remove path length limitation
  - fix compilation errors and warning, fix static analysis reports
  - reformat of the code for readability and consistency

There are also branches keeping history of patches that I did not
merge (yet?).

I’ll tag a release in a few days (weeks?) to let the time for people
to comment, then my intent is to have this new version pushed to
distros.

I have been unable to find development history prior to 0.5.1. If you
have it, I’d be interested for archival purposes.

Best regards,

-- Antonin Décimo