feat(compile): Add option for clean compile environment

[jcs090218]

For #162.

eask compile

Compiling d:/_workspace/test-1/eask-test.el... done
Compiling d:/_workspace/test-1/one.el... done
Compiling d:/_workspace/test-1/two.el... done

(Total of 3 files compiled, 0 skipped)

eask compile --clean

Compiling d:/_workspace/test-1/eask-test.el... done
Compiling d:/_workspace/test-1/one.el... done
Compiling d:/_workspace/test-1/two.el... skipped

In end of data:
two.el:3:2: Warning: the function `-filter' is not known to be defined.

(Total of 2 files compiled, 1 skipped)

eask compile --help

  compile [names..]

  Byte compile all Emacs Lisp files in the package

  Positionals:
    [names..]  specify files to byte-compile

+ Command Options:
+   -c, --clean  clean byte-compile files individually                                                                                                                                                    [boolean]

  Proxy Options:
        --proxy        update proxy for HTTP and HTTPS to host                                                                                                                                             [string]
...