resource: Add Match and GetMatch

These methods takes a glob pattern as argument:

* by default matching from the bundle root
* matching is case insensitive and the separator is Unix style slashes: "/"
* the bundle root does (by default) not start with a leading slash
* if you renames the `Name` for the rsource in front matter (`src=...`), then that is the value used in `Match`.
* double asterisk matches beyond directory borders, so "**.jpg" will match any JPEG image in the bundle

See https://github.com/gobwas/glob

This commit also deprecates `ByPrefix` and `GetByPrefix`.

This should also be more effective, given a fair amount of reuse of the glob patterns:

```bash
BenchmarkResourcesByPrefix-4         300000          4284 ns/op        1130 B/op           7 allocs/op
BenchmarkResourcesMatch-4            300000          5220 ns/op         505 B/op           3 allocs/op
```

Fixes #4301

1 files changed, 4 insertions, 0 deletions

diff --git a/Gopkg.toml b/Gopkg.toml
index 5218dc3af..b07a41f7c 100644
--- a/Gopkg.toml
+++ b/Gopkg.toml
@@ -131,3 +131,7 @@
 [[constraint]]
   branch = "v2"
   name = "gopkg.in/yaml.v2"
+
+[[constraint]]
+  name = "github.com/gobwas/glob"
+  version = "0.2.2"