add vars to sample env

Adding vars to the sample env for profile fields, display name characters, max image and video size, and max audio clip length

.env.production.sample

@@ -160,6 +160,21 @@ STREAMING_CLUSTER_NUM=1
 # Maximum number of pinned posts
 # MAX_PINNED_TOOTS=10
 
+# Maximim number of profile fields allowed
+# MAX_PROFILE_FIELDS=4
+
+# Maximum allowed display name characters
+# MAX_DISPLAY_NAME_CHARS=30
+
+# Maximum image and video upload sizes
+# Units are in bytes
+# 1048576 bytes equals 1 megabyte
+# MAX_IMAGE_SIZE=8388608
+# MAX_VIDEO_SIZE=41943040
+
+# Maximum length of audio uploads in seconds
+# MAX_AUDIO_LENGTH=60
+
 # LDAP authentication (optional)
 # LDAP_ENABLED=true
 # LDAP_HOST=localhost