Merge Development (globalsign#57)

* add DropAllIndexes() method (globalsign#25)

Create a new method to drop all the indexes of a collection
in a single call

* readme: credit @feliixx for globalsign#25 (globalsign#26)

* send metadata during handshake (globalsign#28)

fix [#484](https://github.com/go-mgo/mgo/issues/484)

Annotate connections with metadata provided by the
connecting client.

informations send:

{
 "aplication": {         // optional
   "name": "myAppName"
 }
 "driver": {
    "name": "mgo",
    "version": "v2"
  },
  "os": {
    "type": runtime.GOOS,
    "architecture": runtime.GOARCH
  }
}

to set "application.name", add `appname` param in options
of string connection URI,
for example : "mongodb://localhost:27017?appname=myAppName"

* Update README to add appName (globalsign#32)

* docs: elaborate on what appName does

* readme: add appName to changes

* add method CreateView() (globalsign#33)

Fix globalsign#30.

Thanks to @feliixx for the time and effort.

* readme: credit @feliixx in the README (globalsign#36)

* Don't panic on indexed int64 fields (globalsign#23)

* Stop all db instances after tests (go-mgo#462)

If all tests pass, the builds for mongo earlier than 2.6 are still failing.
Running a clean up fixes the issue.

* fixing int64 type failing when getting indexes and trying to type them

* requested changes relating to case statement and panic

* Update README.md to credit @mapete94.

* tests: ensure indexed int64 fields do not cause a panic in Indexes()

See:
* globalsign#23
* https://github.com/go-mgo/mgo/issues/475
* go-mgo#476

* Add collation option to collection.Create() (globalsign#37)

- Allow specifying the default collation for the collection when creating it.
- Add some documentation to query.Collation() method.

fix globalsign#29

* Test against MongoDB 3.4.x (globalsign#35)

* test against MongoDB 3.4.x

* tests: use listIndexes to assert index state for 3.4+

* make test pass against v3.4.x

  - skip `TestViewWithCollation` because of SERVER-31049,
    cf: https://jira.mongodb.org/browse/SERVER-31049

  - add versionAtLeast() method in init.js script to better
    detect server version

fixes globalsign#31

* Introduce constants for BSON element types (globalsign#41)

* bson.Unmarshal returns time in UTC (globalsign#42)

* readme: add missing features / credit

* Adds missing collation feature description (by @feliixx).
* Adds missing 3.4 tests description (by @feliixx).
* Adds BSON constants description (by @bozaro).
* Adds UTC time.Time unmarshalling (by @gazoon).

* fix golint, go vet and gofmt warnings (globalsign#44)

Fixes globalsign#43

* readme: credit @feliixx (globalsign#46)

* Fix GetBSON() method usage (globalsign#40)

* Fix GetBSON() method usage

Original issue
---

You can't use type with custom GetBSON() method mixed with structure field type and structure field reference type.

For example, you can't create custom GetBSON() for Bar type:

```
struct Foo {
	a  Bar
	b *Bar
}
```

Type implementation (`func (t Bar) GetBSON()` ) would crash on `Foo.b = nil` value encoding.

Reference implementation (`func (t *Bar) GetBSON()` ) would not call on `Foo.a` value encoding.

After this change
---

For type implementation  `func (t Bar) GetBSON()` would not call on `Foo.b = nil` value encoding.
In this case `nil` value would be seariazied as `nil` BSON value.

For reference implementation `func (t *Bar) GetBSON()` would call even on `Foo.a` value encoding.

* Minor refactoring

* readme: credit @bozaro (globalsign#47)

* Improve cursorData struct unmarshaling speed (globalsign#49)

This change remove full BSON decoding on:

 - parsing to `bson.Raw` and `bson.DocElem` fields;
 - skipping unused BSON fields.

* readme: credit @bozaro and @idy (globalsign#53)

* readme: credit @bozaro and @idy

* readme: add @idy to contributor list

* do not lock while writing to a socket (globalsign#52) (globalsign#54)

fix globalsign#51

README.md

@@ -30,6 +30,8 @@ Further PR's (with tests) are welcome, but please maintain backwards compatibili
 * Consistently unmarshal time.Time values as UTC ([details](https://github.com/globalsign/mgo/pull/42))
 * Enforces best practise coding guidelines ([details](https://github.com/globalsign/mgo/pull/44))
 * GetBSON correctly handles structs with both fields and pointers ([details](https://github.com/globalsign/mgo/pull/40))
+* Improved bson.Raw unmarshalling performance ([details](https://github.com/globalsign/mgo/pull/49))
+* Minimise socket connection timeouts due to excessive locking ([details](https://github.com/globalsign/mgo/pull/52))
 
 ---
 
@@ -42,6 +44,7 @@ Further PR's (with tests) are welcome, but please maintain backwards compatibili
 * @eaglerayp
 * @feliixx
 * @fmpwizard
+* @idy
 * @jameinel
 * @gazoon
 * @mapete94

bson/bson_test.go

@@ -82,6 +82,19 @@ func testUnmarshal(c *C, data string, obj interface{}) {
 	err := bson.Unmarshal([]byte(data), zero)
 	c.Assert(err, IsNil)
 	c.Assert(zero, DeepEquals, obj)
+
+	testUnmarshalRawElements(c, []byte(data))
+}
+
+func testUnmarshalRawElements(c *C, data []byte) {
+	elems := []bson.RawDocElem{}
+	err := bson.Unmarshal(data, &elems)
+	c.Assert(err, IsNil)
+	for _, elem := range elems {
+		if elem.Value.Kind == bson.ElementDocument || elem.Value.Kind == bson.ElementArray {
+			testUnmarshalRawElements(c, elem.Value.Data)
+		}
+	}
 }
 
 type testItemType struct {