rename the remaining plain structs

rename the remaining plain structs

struct b64_context            struct B64Context
struct binding_t              struct Binding
struct browser_state          struct BrowserState
struct command_t              struct Command
struct compile_options        struct CompileOptions
struct coord                  struct Coord
struct crypt_cache            struct CryptCache
struct crypt_module_functions struct CryptModuleFunctions
struct crypt_module_specs     struct CryptModuleSpecs
struct dn_array_s             struct DnArrayS
struct enriched_state         struct EnrichedState
struct extkey                 struct Extkey
struct fgetconv_not           struct FgetConvNot
struct fgetconv_s             struct FgetConvS
struct folder_file            struct FolderFile
struct hash_elem              struct HashElem
struct hash_walk_state        struct HashWalkState
struct hdr_format_info        struct HdrFormatInfo
struct header_cache           struct HeaderCache
struct history                struct History
struct keymap_t               struct Keymap
struct line_t                 struct Line
struct maildir                struct Maildir
struct mapping_t              struct Mapping
struct md5_ctx                struct Md5Ctx
struct mh_data                struct MhData
struct mh_sequences           struct MhSequences
struct m_update_t             struct MUpdate
struct mx_ops                 struct MxOps
struct nm_ctxdata             struct NmCtxdata
struct nm_hdrdata             struct NmHdrdata
struct nm_hdrtag              struct NmHdrtag
struct option_t               struct Option
struct pattern_flags          struct PatternFlags
struct pgp_cache              struct PgpCache
struct pgp_command_context    struct PgpCommandContext
struct q_class_t              struct QClass
struct range_regexp           struct RangeRegex
struct resize                 struct Resize
struct rfc2231_parameter      struct Rfc2231Parameter
struct smime_command_context  struct SmimeCommandContext
struct syntax_t               struct Syntax
struct sysexits               struct Sysexits
struct _tlssockdata           struct TlsSockData
struct tz_t                   struct Tz
struct uri_tag                struct UriTag