Reorganize packages, closes #79

- All packages go into either cmd or pkg directories
- Most packages renamed
- Server packages moved into pkg/server
- sanitize moved into webui, as that's the only place it's used
- filestore moved into pkg/storage/file
- Makefile updated, and PKG variable use fixed

pkg/server/web/context.go

@@ -0,0 +1,68 @@
+package web
+
+import (
+	"net/http"
+	"strings"
+
+	"github.com/gorilla/mux"
+	"github.com/gorilla/sessions"
+	"github.com/jhillyerd/inbucket/pkg/config"
+	"github.com/jhillyerd/inbucket/pkg/msghub"
+	"github.com/jhillyerd/inbucket/pkg/storage"
+)
+
+// Context is passed into every request handler function
+type Context struct {
+	Vars      map[string]string
+	Session   *sessions.Session
+	DataStore datastore.DataStore
+	MsgHub    *msghub.Hub
+	WebConfig config.WebConfig
+	IsJSON    bool
+}
+
+// Close the Context (currently does nothing)
+func (c *Context) Close() {
+	// Do nothing
+}
+
+// headerMatch returns true if the request header specified by name contains
+// the specified value.  Case is ignored.
+func headerMatch(req *http.Request, name string, value string) bool {
+	name = http.CanonicalHeaderKey(name)
+	value = strings.ToLower(value)
+
+	if header := req.Header[name]; header != nil {
+		for _, hv := range header {
+			if value == strings.ToLower(hv) {
+				return true
+			}
+		}
+	}
+
+	return false
+}
+
+// NewContext returns a Context for the given HTTP Request
+func NewContext(req *http.Request) (*Context, error) {
+	vars := mux.Vars(req)
+	sess, err := sessionStore.Get(req, "inbucket")
+	if err != nil {
+		if sess == nil {
+			// No session, must fail
+			return nil, err
+		}
+		// The session cookie was probably signed by an old key, ignore it
+		// gorilla created an empty session for us
+		err = nil
+	}
+	ctx := &Context{
+		Vars:      vars,
+		Session:   sess,
+		DataStore: DataStore,
+		MsgHub:    msgHub,
+		WebConfig: webConfig,
+		IsJSON:    headerMatch(req, "Accept", "application/json"),
+	}
+	return ctx, err
+}