Remove mention of the removed commands

[XVilka]

See rizinorg/rizin@9586737 and rizinorg/rizin@8810586

• Remove join command
• Remove head command
• Remove less and directly list ls command
• Remove T commands and log related functions
• Remove u commands and Q alias
• Remove : commands
• Remove ' command (alias for =!)
• Remove \ (alias for =!) command
• Remove m commands

[XVilka]

Partially done in 97e35f3

[officialcjunior]

I think, a lot of them haven't even been added to the book for us to remove, from what I can see.
I searched for a few.
l will continue looking for them. If someone already knows where it could be present, just point it out so that I can get it done.

[FortStatement]

Also pdc from rizinorg/rizin#105 -
Still present in ioli_0x02 and Comparing Bytes

[officialcjunior]

Should we just remove that part? It also has an instance of r2dec.

[wargio]

yes, probably, unless you want to update it with a section related to the decompilers (jsdec and rz-ghidra)