[PR #1898] Added README entry about installing through SPM.
[PR #1898] Added README entry about installing through SPM.


Noobish1/Alamofire,Lomotif/Alamofire,Alamofire/Alamofire,richardPFisk/Alamofire,easyui/Alamofire,yimajo/Alamofire,Noobish1/Alamofire,antigp/Alamofire,iosheadhunter/Alamofire,yimajo/Alamofire,richardPFisk/Alamofire,Alamofire/Alamofire,jschmid/Alamofire,easyui/Alamofire,Farteen/Alamofire,jschmid/Alamofire,antigp/Alamofire,Lomotif/Alamofire,Farteen/Alamofire,iosheadhunter/Alamofire