feat(bin): Up Subcommand

[refcell]

Description

As part of #17, this task is to move the Stack logic in stack.rs to an up subcommand. Most of the time, op-up will be run without specifying this subcommand since it is redundant to execute op-up up.

The up subcommand itself should have a --devnet flag that can be used to override the local stack.toml and default config for a hard-coded devnet stack configuration.

Since this subcommand will have flags and some additional logic, it should be moved to a new up.rs file. So, just moving the contents of stack.rs to this new file and then dispatching the top-level cli.rs to this handler by default and when the up subcommand is provided.

[merklefruit]

Closed in #38