pattern rule not working with all scalar types

### Environment

* Python version: 3.6.9
* PyKwalify version: 1.7.0

Documentation states the pattern rule works for all scalar types.
It appears that with the commit for issue #47, the pattern rule only works for string values.

### Steps to Reproduce

1. pykwalify -s schema.yaml -d data.yaml

### Schema

```
type: map
mapping:
"=":
type: scalar
pattern: .*
```

### Data

```
boolean: true
number: 1
string1: truE
string2: 127.0.0.1
```

### Expected Behavior
Validation passes.

### Observed Behavior

```
ERROR - validation.invalid
ERROR - --- All found errors ---
ERROR - [u"Value 'True' does not match pattern '.*'. Path: '/boolean'", u"Value '1' does not match pattern '.*'. Path: '/number'"]
Traceback (most recent call last):
File "/usr/local/bin/pykwalify", line 11, in
sys.exit(cli_entrypoint())
File "/usr/local/lib/python2.7/dist-packages/pykwalify/cli.py", line 95, in cli_entrypoint
run(parse_cli())
File "/usr/local/lib/python2.7/dist-packages/pykwalify/cli.py", line 82, in run
c.validate()
File "/usr/local/lib/python2.7/dist-packages/pykwalify/core.py", line 167, in validate
error_msg=u'.\n - '.join(self.validation_errors)))
pykwalify.errors.SchemaError:
```