Add screen 1F5B5, and various improvements

[nataliakeniganti]

A src vector for the screen (codepoint 1F5B5) has been added, as suggested in the discussion in #563

Additionally, several src vectors have been modified:

• Fix the hour hand in three-thirty
• Fix warning between line and dot

This pull request should hopefully fully address the following issue:

• Clock face of half hours is just plain wrong #566
• warning / ⚠️ / 26A0 should maybe have more space between line and dot #568

[b-g]

@nataliakeniganti many thanks for this! Happy to merge the three-thirty one straight away ... but the TV seems to be less readable and clear in comparison to https://openmoji.org/library/emoji-1F4FA/, could you elaborate what kind of screen we are talking about?

[nataliakeniganti]

@nataliakeniganti many thanks for this! Happy to merge the three-thirty one straight away ... but the TV seems to be less readable and clear in comparison to https://openmoji.org/library/emoji-1F4FA/, could you elaborate what kind of screen we are talking about?

Fixed metadata.

[jneb]

What about the other half-past clocks? They're all wrong!