Chemical Compositions, and Antimicrobial and Mosquito Larvicidal Activities of Essential Oils from Four <i>Syzygium</i> Species <i>Syzygium formosum</i> (Wall.) Masam., <i>S. syzygioides</i> (Miq.) Merr. &amp; L.M. Perry, <i>S. megacarpum</i> (Craib) Rathakr. &amp; N.C. Nair, and <i>S. chantaranothaianum</i> W.K. Soh &amp; J. Parn