[#1180] Extract to-be-signed pcrim data

[chubtub]

These changes comprise two new actions:

1. Print base RIMs as unformatted XML by default. Whitespace added for human-readability renders base RIMs unparseable by outside XML tools. A human readable form can be displayed separately via the rim print command.
2. Support an -x|--extract argument, to parse the to-be-signed data from a signed base RIM. The parsed results are written to a file of the same name as the base RIM with "_toBeSigned" appended.

Closes #1180