In an effort to be more consistent about encoding parameters for GET
requests made in the script which generates electoral rolls and some
event invite lists, centralize calls to the requests module. This
has the added benefit of encapsulating retry logic for potential
reuse in later additions to the script.
Also generalize the query_gerrit() function to flexibly handle both
Gerrit REST API which return neutered JSON and Gerrit Gitweb queries
for retrieving YAML with its own special character encoding
challenges.
Further extract out the JSON decoder error handling so it can be
reused for other APIs than Gerrit's in future feature additions.
Change-Id: Ibda65d41c17416eb28eb326e2cdd28c90153f108
5b8df42959