Move bash argv opt to end of ags line in scripts

see #113 (closed)

The $@ option in bash doesn't make sense to come before generate because the only option we can pass before generate cli usage is help.

System properties can be passed via JAVA_OPTS, so there's not really a need for any intermediaries in the command line construction.

Having $@ at the end of the arguments list allows maintainers and users inspecting options to quickly pass new options to a script. For example,

./bin/aspnetcore-petstore.sh --additional-properties sourceFolder=asdf

For command line arguments that may appear more than once in the arguments list, this change doesn't provide any rules about overwriting values that may exist (hard-coded) in the script. That is, in the example above, if aspnetcore-petstore.sh already includes the sourceFolder set to a different value, the "winning" value is up to the options parser and openapi-generator-cli implementation.

PR checklist

• Read the contribution guidelines.
• Ran the shell script under ./bin/ to update Petstore sample so that CIs can verify the change. (For instance, only need to run ./bin/{LANG}-petstore.sh and ./bin/security/{LANG}-petstore.sh if updating the {LANG} (e.g. php, ruby, python, etc) code generator or {LANG} client's mustache templates). Windows batch files can be found in .\bin\windows\.
• Filed the PR against the correct branch: Default: master.
• Copied the technical committee to review the pull request if your PR is targeting a particular programming language.