[feature] Document hover for pseudo Instruction

[Freed-Wu]

For the pseudo instructions, .globl, .long, can the language server provide a hover to display their usage to save users' time to search the manual? All pseudo instructions can be found in https://sourceware.org/binutils/docs-2.41/as/index.html.

[WillLillis]

This would be a great addition! We'll have to write some scripts to grab the information off of the site you linked and convert it into a .xml file the program can read, but beyond that adding support should be relatively easy.