IS_LANG_UPD && trailing spaces

[vladsavchuk]

If I have trailing spaces inside backticks of multi-language string, the lang file continues to be updated on every request:

`Space trailing `
` Space leading`
` Space both `

en.txt keeps growing with:

Space trailing  ===.
 Space leading ===.
 Space both  ===.
Space trailing  ===.
 Space both  ===.
Space trailing  ===.
 Space both  ===.
Space trailing  ===.
 Space both  ===.
Space trailing  ===.
 Space both  ===.
Space trailing  ===.
 Space both  ===.
Space trailing  ===.
 Space both  ===.
Space trailing  ===.
 Space both  ===.
Space trailing  ===.
 Space both  ===.