628 make text to centreline case insensitive

[gabrielwol]

What this pull request accomplishes:

3 modified and 1 new function to make text_to_centreline case insensitive.

• new function: custom_case: new function to selectively capitalize/lowercase certain words
• gis._clean_bylaws_text: lots of whitespace changes, call custom_case on input params, add some variables to simplify a few blocks.
• abbr_street: make some replacements case insensitive
• _translate_intersection_point: match lower or upper and abbreviated or full cardinal directions

Issue(s) this solves:

• Closes #628

What, in particular, needs to reviewed:

• Lots of changes but see test cases below! Seems to be working!

What needs to be done by a sysadmin after this PR is merged

E.g.: these tables need to be migrated/created in the production schema.