Round the focal length value from EXIF when displayed

[roytanck]

It appears that the EXIF data focal length value is displayed as is. Sometimes this value is very precise, something like "5.6999998092651mm".

Example: ​https://wordpress.org/photos/photo/98665b56c9/

Can we perhaps round this number to two decimals? I feel that would still be accurate enough, and look much better.

[roytanck]

Screenshot of a long focal length value.

fixes: https://meta.trac.wordpress.org/ticket/7427

[coffee2code]

In 13155:

Photo Directory, Photo: Round focal length value to at most two decimal places if greater precision is provided.

Props benniledl, roytanck, coffee2code.
Fixes #7427.
Fixes ​https://github.com/WordPress/wordpress.org/pull/196

[dd32]

In 13156:

Photo Directory, Photo: Use break instead of continue within switch.

Avoids a PHP warning: E_WARNING: "continue" targeting switch is equivalent to "break". Did you mean to use "continue 2"?

Introduced in [13155].
See #7427.