add: project Dockerfile

[atezs82]

Thanks for the awesome project!

I tried to install & run on MacOS Big Sur but after installing the Rust compiler got this error (when executing pip3 install git+https://github.com/ramsrigouthamg/Questgen.ai and installing tokenizers==0.8.1.rc1):

error[E0658]: `if` is not allowed in a `const fn`
    --> /Users/attila.toth/.cargo/registry/src/github.com-1ecc6299db9ec823/clap-2.34.0/src/app/settings.rs:7:1
     |
  7  | / bitflags! {
  8  | |     struct Flags: u64 {
  9  | |         const SC_NEGATE_REQS       = 1;
  10 | |         const SC_REQUIRED          = 1 << 1;
  ...  |
  51 | |     }
  52 | | }
     | |_^
     |
     = note: see issue #49146 <https://github.com/rust-lang/rust/issues/49146> for more information
     = help: add `#![feature(const_if_match)]` to the crate attributes to enable
     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)

  error[E0658]: `if` is not allowed in a `const fn`
    --> /Users/attila.toth/.cargo/registry/src/github.com-1ecc6299db9ec823/clap-2.34.0/src/args/settings.rs:6:1
     |
  6  | / bitflags! {
  7  | |     struct Flags: u32 {
  8  | |         const REQUIRED         = 1;
  9  | |         const MULTIPLE         = 1 << 1;
  ...  |
  28 | |     }
  29 | | }
     | |_^
     |
     = note: see issue #49146 <https://github.com/rust-lang/rust/issues/49146> for more information
     = help: add `#![feature(const_if_match)]` to the crate attributes to enable
     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)

So in order to make this work I have created a small Dockerfile to overcome this, also slightly modified the README.md if anyone else runs into this issue as well. Please see the attached PR, let me know if you have any comments!