Make override conventions an optional command

[walmon]

For example, right now creating a model or a controller by default overrides the folder convention, creating files in the current folder.

conv generate model conv generate controller should accept [-h --here] with yes - no options. Default should be no.

If -h is set to yes, then require which chaincode project (inside ./packages folder) to receive the new file through [-p --project] param with the chaincode package project name.

Result expected:

Assuming the current structure is ./myproject/packages/coffeechain whereas coffeechain folder is a chaincode project.

# Creates file in `./`
conv generate model myToken -h yes

# Creates file in `./packages/coffeechain`
conv generate model myToken -h yes -p coffeechain