Petitboot v1.4.0 & v1.4.1 tagged

[Samuel Mendoza-Jonas]

Petitboot v1.4.0 and v1.4.1 have been tagged.

Petitboot v1.4.0 was technically tagged in December and it turns out I never
quite found a moment to write some release notes. The 31 patches between v1.3.2
and v1.4.0 are part of one large set to improve the readability and information
content of the Petitboot UI, namely:

- Addition of a new 'status log' screen
A new screen holds a full backlog of all status messages sent by pb-discover.
This backlog is also available after exiting and restarting the UI.

- Improved relevance of status messages
Several status messages are added, clarified, or removed to be more useful to
the user. This also includes the addition of a number of internal helper
functions to make the addition of new messages easier.

- Live reporting of download progress
lib/process and discover/paths are extended to support live handling of the
output from asynchronous processes. For utilities concerned with file transfer
(tftp, wget, etc) this allows pb-discover to track download progress. For
small configuration files this is usually instant but becomes much more useful
when tracking the download of larger files such as the kernel and initrd during
boot.


Petitboot v1.4.1 contains the following fixes over v1.4.0:

Fixing potential segfaults in pb-discover depending on configuration:
- process: Cancel all asynchronous jobs on reinit,
- discover/device-handler: Cancel pending boot on reinit,
- discover/network: Ensure interfaces have device before configuring, and
- discover/network: Search by UUID only if available

Fixes an issue where an otherwise valid boot option would never resolve:
- discover/device-handler: Process queue after device added

Fixes an issue when running on peculiar machines:
- discover/network: Ignore interfaces with pre-existing MAC address