Make naming and formatting of blocks and their fields consistent

[Pwuts]

Our automatic "pretty" formatting of field and block names isn't great. Examples:

• "Read Csv Block"
• "Request Url"
• "Api Key"
• "Rss Url"

These should be set explicitly rather than generated from a class/field name or type name, and imo we also should not be auto-capitalizing every word because aesthetically it just doesn't work.

TODO

• Fix naming of block classes (e.g. ReadCsvBlock ("Read Csv Block") -> ReadCSVBlock ("Read CSV Block")
• Add title parameter to Block.__init__ which overrides the auto-formatted title, to be used if our prettifying algorithm isn't compatible with the intended block title
• Set explicit title on fields that currently aren't properly formatted (e.g. "Request Url", "Api Key")