various tutorial cleanups

[SysPete]

Changes proposed:

• prefer C<< >> to using =E inside C< > for readability of raw pod
• consistent alignment of code and css in examples
• make sure all =head are followed by a blank line
• set encoding to utf8
• always break or die onto following line for consistency in examples
• remove unnecessary quotes around string before fat comma in examples
• some small changes to punctuation, mostly replacement of -

[SysPete]

Hat tipped to @tomhukins for pointing out some of the issues.

[cromedome]

Thank you! :+1: