Use shared code, and fix a variety of issues

[jpmckinney]

I started this PR to use a common build across profiles, but ended up finding and fixing a variety of issues along the way:

• tag enum not matching the changes to the releaseTag codelist
• Line breaks inside codelist rows, without appropriate quoting
• Invalid collapse values in jsonschema directives
• A broken RST table in framework.md
• Mis-capitalized or suffixed codelist headers
• Blank lines in codelists
• Inconsistent use of contract/implementation versus "contract, implementation" in documentType.csv Section column
• Missing codelists property in extension.json
• Typos in codes and fields in the documentation
• Typos in documentation and codelist descriptions

The above issues would: affect (or break) the correct parsing of those codelists, mis-render (or not render) elements of the docs, and/or introduce ambiguity which could lead to errors in implementation. So, I think this is important to merge.

This PR also includes #63.

Use https://github.com/open-contracting/public-private-partnerships/pull/121/files?w=1 to ignore whitespace changes.

When reviewing the PR, you can skip all the following files using the "Jump to…" dropdown, as these are generated from other files (by copying or by script):

• compiledCodelists (36 files)
• docs/extensions (19 files), but don't skip milestones.md, which is not generated (index.md is also not generated, but it is unchanged)
• docs/extensions/codelists (16 files)
• schema/base-codelists (20 files)
• schema/base-release-schema.json
• schema/ppp-extension.json
• schema/ppp-release-schema.json

Another 9 files are part of the build and not part of the docs, and don't require as close a review, as what matters is what gets built. Another 2 files are example files with typo and whitespace corrections.

So, that leaves only 20 substantive files to review, all of which are quite fast to review as the changes are minor (but sometimes important).

[jpmckinney]

@duncandewhurst We can perhaps schedule a call to review; there are a lot of commits, but it shouldn't take to long to review on a call. Several other issues/PRs depend on merging this.

[jpmckinney]

Approved PR with @duncandewhurst. The "latest" branch at http://standard.open-contracting.org/profiles/ppp/latest/ won't be affected as we still need to manually copy the built documentation, which we'll do after sorting translations.