v2.0

At last, the rewrite is complete! (no binaries as of yet)

• New redirection COMMANDS, with more predictable behaviour
• Use extended regex in switch statements
• Bugfix: Job control
• Bugfix: Very long pipe streams no longer deadlock. The first n-1 chained commands of an n-long pipeline are now always forked off as separate processes.
• Array substitution is now ${name key} (temporary change, old syntax will return)
• New str command (replaces string)
• New arr command (replaces array)
• New BUILT-IN list command (no longer part of stdlib)
• Speaking of stdlib, it has been removed (why not just use .? It's a shell, not C++)
• Nicer codebase in general

To-do:

• Re-add regexp, maybe regcomp
• Add unknown feature, similar to Tcl.
• Re-add old array syntax $...(...)
• Improve performance