acl: Add and use ACL_USER_CONTEXT_REQUIRE Satisfies static analyzers

acl: Add and use ACL_LIST_CONTEXT_REQUIRE Satisfies static analyzers

acl: Contexts are now required or checked Satisfies static analyzers

acl: If acl_user is set, use it for ACL username checks. Overrides master_user.

acl: Added ACL checks for attributes. Added ACL <-> mailbox attribute mapping. The ACL checks will be useful once IMAP METADATA extension is finished. The mapping is used by dsync to sync ACLs via generic attribute syncing.

Marked functions parameters that are allowed to be NULL. Some APIs were also changed. The non-obvious APIs where NULL parameter was changed to "" are master_service_init() and auth_master_user_list_init(). These checks can currently be enabled only on a patched clang: http://llvm.org/bugs/show_bug.cgi?id=6786

acl: Fixed listing multiple shared namespaces.

acl: Override mailbox list functions in mailbox_list_created hook.

lib-storage: Plugin API changed to run plugin functions in correct order. Previously the hooks were run in correct order, but the functions they overrode were run in reverse order. This caused problems when multiple plugins were used. --HG-- branch : HEAD

plugins: Simplified code by using mailbox_allocated hook. --HG-- branch : HEAD

plugins: Use mail_namespace_storage_added hook instead of mailbox_list_created. In mailbox_list_created the storage hasn't yet overridden the list functions. --HG-- branch : HEAD

lib-storage: Plugin hook API changed to support per-user plugins within a process. --HG-- branch : HEAD

Mailbox opening and closing APIs changed. --HG-- branch : HEAD

Initial commit for making mail_storage:mailbox_list to be from 1:1 to n:n. This will allow namespaces to share the same storage and a single namespace to have multiple storages (multiple mailbox formats). Neither works currently, and this commit probably breaks some things. --HG-- branch : HEAD

Initial support for LISTing users with shared mailboxes. --HG-- branch : HEAD

Added IMAP ACL commands with ability to modify ACLs. Based on patch by Bernhard Herzog and Sascha Wilde. --HG-- branch : HEAD

acl: Fixed handling 'k' right. Although box/child creation was prevented, box/child/child wasn't. --HG-- branch : HEAD

Changed .h ifdef/defines to use <NAME>_H format. --HG-- branch : HEAD

acl_backend is now tied to mailbox_list instead of mail_storage. --HG-- branch : HEAD

Better type safety to module_contexts arrays. Already fixed some bugs. --HG-- branch : HEAD

Initial code for separation of mailbox accessing and directory layout handling. It's not yet possible to change the default layouts though. --HG-- branch : HEAD

Array API redesigned to work using unions. It now provides type safety without having to enable DEBUG, as long as the compiler supports typeof(). Its API changed a bit. It now allows directly accessing the array contents, although that's not necessarily recommended. Changed existing array usage to be type safe in a bit more places. Removed array_t completely. Also did s/modifyable/modifiable/. --HG-- branch : HEAD

Added initial support for ACLs. Currently supports reading the ACLs from files. Since no proper support for shared folders exist yet, this is mostly intended to be used only for preventing users from fully accessing the mailboxes they'd otherwise have full access to. It anyway does support "master user" having different ACLs to mailboxes. --HG-- branch : HEAD