Introduce nob_filepath_match() & enhance nob_read_entire_dir()

[gaogao-qwq]

Just like #114. This pr introduce nob_filepath_match() which similar to Go's path.Match() or GNU Make's ($wildcard pattern...). And enhanced nob_read_entire_dir() with .recursively and .wildcard options without breaking forward compability.

e.g.

.
├── external
│   ├── foobar
│   │   ├── foobar.h
│   │   ├── libfoobar.a
│   │   └── libfoobar.so
│   └── foobarbaz
│       ├── foobarbaz.h
│       ├── libfoobarbaz.a
│       └── libfoobarbaz.so
├── include
│   ├── bar
│   │   └── bar.h
│   ├── baz.h
│   └── foo
│       └── foo.h
└── src
    ├── bar
    │   └── bar.c
    ├── baz.c
    └── foo
        └── foo.c

nob_read_entire_dir(".", &children, .recursively = true, .wildcard = "./src/*.c"):
    ./src/baz.c
nob_read_entire_dir(".", &children, .recursively = true, .wildcard = "./src/**/*.c"):
    ./src/bar/bar.c
    ./src/foo/foo.c
nob_read_entire_dir(".", &children, .recursively = true, .wildcard = "./external/**/*.so"):
    ./external/foobarbaz/libfoobarbaz.so
    ./external/foobar/libfoobar.so