Rename buildheap executable

[xrchz]

When looking at running processes while Holmake or hol is running there's something called buildheap that is actually the name of the hol process. This issue is to name it hol or something more descriptive/recognisable instead.

[xrchz]

From discussion on Zulip, I am gathering some more specific desiderata:

• Combine the buildheap and hol executables into a single executable (hol) that uses subcommands (commandline arguments) to select what functionality is required
• Remove the shell wrapper, make the executable do everything it needs to without a wrapper

[mn200]

The important current use-cases:

• hol repl starts the repl for interactive proof
• hol lsp starts an LSP server
• hol buildheap builds a heap
• hol runscript runs a script file for building a theory

This seems fairly clean. The repl sub-command could be made optional so that hol on its own just starts the standard REPL (if you want additional options to that invocation, you might insist that repl subcommand be present textually). There might be some value in keeping hol.bare as a shell-script because it would correspond to hol repl --bare or similar.

[digama0]

I don't see the advantage of hol.bare over hol --bare

[mn200]

Two fewer characters and it's just a single token, duh. :-)

But yes, if you just scan all the arguments and don't find a sub-command, assuming repl to be the sub-command is simple to explain and implement.