Remove the --param-file flag

[vdice]

As mentioned in #1053:

Replace/deprecate param file

Currently, the --param-file flag on action commands (porter install, etc.) allows only for a key=value listing for parameters.

This same functionality will be retained in the parameter set file (--parameter-set myparamset), as it has support for value source.

AC:

• Remove the existing --param-file functionality, which will have been replaced by the parameter set file. (Ref feat(*): introduce Parameter Set #1068)

Depends on/should wait for #1068 to be merged.