Set snap name to a human readable name in store upload

[Stuart Langridge]

A snap's name, when publishing it to the store, should be a "nice", human-readable name ("Adobe Photoshop", not the "computer name" of "adobe-photoshop"). By default, when publishing a snap to the store, the "name" field defaults to the "snap name" which is used to install from the command line, i.e., "adobe-photoshop". Since names should be human-readable, it may be a subtle encouragement to do that without explicit instructions needed by calculating a "nice" name from the "snap name"; that is, convert "adobe-photoshop" to "Adobe Photoshop" by replacing hyphens with spaces and converting to title case. The user can of course still change that if they want to, but at the moment every user needs to change the name always. Also, the name defaulting to a "computer name" subtly implies that that's the format the name ought to take.

[Oliver Grawert (ogra)]

this has also come up in the forum before:

https://forum.snapcraft.io/t/add-title-to-top-level-metadata/9664