Pijul support

[boozook]

Please support pijul VCS.

One-file markers example:

use pijul_core::{
>>>>>>> 1 [U6ZDQGJG Resetting the mtime of files after unrecords or partial records]
>>>>>>> 2 [U6ZDQGJG Resetting the mtime of files after unrecords or partial records]
    ArcTxn, Base32, ChangeId, ChannelMutTxnT, ChannelRef, ChannelTxnT, MutTxnTExt, TxnT, TxnTExt,
<<<<<<< 2
======= 1 [XTE2JN6S Pinning patches]
    ArcTxn, Base32, ChangeId, ChannelMutTxnT, ChannelRef, ChannelTxnT, GraphTxnT, MutTxnTExt, TxnT,
    TxnTExt,
<<<<<<< 1
};
use pijul_core::{HashMap, HashSet};