Add custom sorting for folders

A new config options for accounts.conf (folders-sort) was added to
allow a user to choose which folders should be shown on top.
My use case was to avoid stepping into heavy, but rarely viewed folders
when cycling through other often accessed ones.

To test add this to your account.conf:

folders-sort  = INBOX,Sent,Archive

INBOX, Sent and Archive should then show at the top of your dirlist,
and all other folders should come next in alphabetical order.

1 files changed, 1 insertions, 0 deletions

diff --git a/config/config.go b/config/config.go
index 32d07fc..dd1f5f4 100644
--- a/config/config.go
+++ b/config/config.go
@@ -61,6 +61,7 @@ type AccountConfig struct {
 	OutgoingCredCmd string
 	SignatureFile   string
 	SignatureCmd    string
+	FoldersSort     []string `ini:"folders-sort" delim:","`
 }
 
 type BindingConfig struct {