Extend template-parameter definition syntax in serverless configuration

[jasonterando]

Support object and array syntax for template-parameters configuration file setting

See description in Issue #258

Description of changes:

Update AmazonLambdaTools to check the parameter type for template-parameters.

• [Current] If it's a string, generate a Dictionary using current syntax ("key1=value1;key2=value2;...keyN=valueN")
• [New] If it's an object, process it using property names for keys and cast values as string
• [New] If it's an array of strings, process it using the syntax supported by SAM, which s a list of "key=value" strings

This approach is backward compatible, it won't break usage of existing template files.

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