Update go-mysql-server dependency

Gopkg.toml

@@ -1,6 +1,6 @@
 [[constraint]]
   name = "gopkg.in/src-d/go-mysql-server.v0"
-  revision = "28b0ab840c6aeb47b77598496ee4fc4aadec7feb"
+  revision = "e8316f5430855f55b0da4b5c63fc990d75c2c085"
 
 [[constraint]]
   name = "github.com/jessevdk/go-flags"

docs/using-gitbase/functions.md

@@ -17,4 +17,4 @@ To make some common tasks easier for the user, there are some functions to inter
 
 ## Standard functions
 
-You can check standard functions in [`go-mysql-server` documentation](https://github.com/src-d/go-mysql-server/tree/28b0ab840c6aeb47b77598496ee4fc4aadec7feb#custom-functions).
+You can check standard functions in [`go-mysql-server` documentation](https://github.com/src-d/go-mysql-server/tree/e8316f5430855f55b0da4b5c63fc990d75c2c085#custom-functions).

docs/using-gitbase/indexes.md

@@ -10,4 +10,4 @@ Note that you can create an index either **on one or more columns** or **on a si
 
 You can find some more examples in the [examples](./examples.md#create-an-index-for-columns-on-a-table) section.
 
-See [go-mysql-server](https://github.com/src-d/go-mysql-server/tree/28b0ab840c6aeb47b77598496ee4fc4aadec7feb#indexes) documentation for more details
+See [go-mysql-server](https://github.com/src-d/go-mysql-server/tree/e8316f5430855f55b0da4b5c63fc990d75c2c085#indexes) documentation for more details

docs/using-gitbase/supported-syntax.md

@@ -1,3 +1,3 @@
 ## Supported syntax
 
-To see the SQL subset currently supported take a look at [this list](https://github.com/src-d/go-mysql-server/blob/28b0ab840c6aeb47b77598496ee4fc4aadec7feb/SUPPORTED.md) from [src-d/go-mysql-server](https://github.com/src-d/go-mysql-server).
+To see the SQL subset currently supported take a look at [this list](https://github.com/src-d/go-mysql-server/blob/e8316f5430855f55b0da4b5c63fc990d75c2c085/SUPPORTED.md) from [src-d/go-mysql-server](https://github.com/src-d/go-mysql-server).