Address issues with offline analysis guide

Address various issues in the offline CBC analysis guide brought up in #96 (closed):

• Order of operations for some steps was not correctly illustrated so could cause problems for someone running the analysis for the first time.
• Generalize usage for generating x509 proxys so it's more portable. (ICDS did things differently than was expected)
• Fix a few commands so they work as-is.
• Word wrap some paragraphs.

added 15 commits

• 7bf043d3...0c1e6b5f - 12 commits from branch master
• b21cbf1a - remove need to have explicit x509_proxy target in template Makefiles for offline workflows
• 3e139878 - docs: update offline cbc workflow to clarify proxy generation
• 8ad1258b - docs: address issues with offline cbc analysis instructions - order of operations, typos, etc

Compare with previous version

merged