Parameter extraction from tempates is error prone

[shonfeder]

The new command extracts parameters from out of a contract template and makes a config file for these params.

The immediate shortcomings in the current parameter extraction are:

• Objects are sometimes not identified correctly, so new sets the parameter with an empty string in the config instead of the proper object.
• There is no way to include any context or documentation to help inform users what the parameters are for.

This might not really be doable in a satisfactorily way for mustache, due to issues like janl/mustache.js#538 (comment)

This was discussed during our walk through of the tool last week.

Related to #48 and #42

[thanethomson]

No longer a problem, given how we've implemented the contract structure in v0.2 (currently on branch prototype/v2, soon to be merged to master).