CS-73: Moved everything to src, changed namespaces

Author: navyasuri

composer.json

@@ -5,18 +5,19 @@
   "keywords": [
     "dapi",
     "dapi-php",
-    "php"
+    "php", 
+    "dapi client"
   ],
   "homepage": "https://github.com/dapi-co/dapi-php",
   "license": "proprietary",
   "require": {
-    "php": ">=7.3",
+    "php": "^7.2.5 || ^8.0",
     "guzzlehttp/guzzle": "^7.3"
   },
   "minimum-stability": "stable",
   "autoload": {
     "psr-4": {
-      "Dapi\\DapiPhp\\": "/"
+      "": "src/"
     }
   },
   "authors": [