Provide Invoice2Data class for object oriented usage

This will allow using invoice2data in an object oriented way like:

import invoice2data

i2d = invoice2data.Invoice2Data()
i2d.extract_data("foo.pdf")

Signed-off-by: Rafał Miłecki <[email protected]>

src/invoice2data/__init__.py

@@ -1 +1,2 @@
 from .main import extract_data  # noqa: F401
+from .main import Invoice2Data  # noqa: F401

src/invoice2data/main.py

@@ -37,6 +37,19 @@
 output_mapping = {"csv": to_csv, "json": to_json, "xml": to_xml, "none": None}
 
 
+class Invoice2Data:
+    def __init__(self, load_built_in_templates=True):
+        self.templates = []
+        if load_built_in_templates:
+            self.templates += read_templates()
+
+    def read_templates(self, path):
+        self.templates += read_templates(os.path.abspath(path))
+
+    def extract_data(self, path, input_module=None):
+        return extract_data(path, self.templates, input_module)
+
+
 def extract_data(invoicefile, templates=None, input_module=None):
     """Extracts structured data from PDF/image invoices.