Updates to metadata checker

[william76]

New meatadata checker features:

Metadata Section Identification

• [x] Add BSSw Metadata tag to the first line of the Metadata comment and have the metadata checker key off that to determine if we're in the metadata comment.
• [ ] Remove the current method for determining if the metadata section is the BSSW metadata in favor of this.

New Categories and Topics

See google document for 'green' highlighted entries. Transitioning these is a two phase process: (1) just add the 'new' tag but don't delete the 'old' property, then (2) we'll remove the 'old' properties later on.

• [x] New publish: preview field should be added. This should also trigger a metadata inspection in addition to publish: yes
• [x] Move Software Engineering from Development to Planning
• [x] Change Development :: Version Control to Development :: Revision Control
• [x] Change Development :: Deployment to Development :: Software Release and Deployment
• [x] Split Development :: Development Tools into Development :: Programming Tools and Development :: Scientific Programming Languages
• [x] Change Performance :: Performance at Leadership Computing Facilities (LCFs) to Performance :: Performance at Leadership Computing Facilities
• [x] Change Collaboration :: Q&A Sites to Collaboration :: Discussion and Question Sites
• [x] Add Collaboration :: Conferences and Workshops as a new topic

GDoc Inconsistencies with Current Ruleset

@curfman I need your input on these:

• [x] Resolve that there is no Planning :: Better Development topic.
• [x] Planning :: Improving productivity and sustainability does not appear in the google document. Is this topic being deprecated?
• [x] Development :: Software Distribution is not a pre-existing rule... is Development :: Software Release and Development a new topic or is it replacing something else? `
• [x] Development :: Deployment is in the current ruleset but does not appear in the google document. Is this the one that is being replaced by Software Distribution?
• [x] Development :: Scientific Programming Languages is shown in the google document to be replacing Programming Languages and Tools, but that rule doesn't exist in the current ruleset. Did you mean this to be replacing Development tools?
• [x] Development :: Programming Tools - same as previous issue about the non existence of Programming Languages and Tools...
• [x] Performance :: Performance at Leadership Computing Facilities inconsistency with existing rule: Performance :: Performance at Leadership Computing Facilities (LCFs) -- which should it be?
• [x] Current ruleset has a Development :: Software engineering topic, but this does not appear in the google document. Is this being deprecated away?

Miscellaneous

• [x] Add footnote to the google doc to note that keeping the source branch around for a while after submitting a PR is helpful because TravisCI will fail if the source branch is deleted before it has a chance to grab and test it. This won't be an issue later on if the tester is made mandatory but for now it's just informational.

FYI @curfman

[william76]

@curfman I made comments on the google document w/rt to consistency with the current ruleset. When you get a chance can you have a look at them and let me know what you think I should change/add?