Add U+06C0 to the Persian layout

In Persian, an isolated form of the letter Ye is added after nouns that are connected to adjectives, and if the noun ends with the letter He, it is often merged with the following Ye, into the letter He with Ye above (U+06C0).

This character exists on the second level of AC05 in the Persian layout of Microsoft Windows, but not in the standard layout. This commit extends the standard layout to include U+06C0 on the third level of AC05.