Resync the Mongolian translation of the Handbook.

MFen:
1.72 -> 1.73 mn_MN.UTF-8/books/handbook/desktop/chapter.sgml
1.29 -> 1.30 mn_MN.UTF-8/books/handbook/geom/chapter.sgml
1.358 -> 1.360 mn_MN.UTF-8/books/handbook/install/chapter.sgml

Submitted by: Ganbold Tsagaankhuu, ganbold at micom.mng.net