intergrate rt130

closes #70 (closed)

• Change folders'name: model/reftek => model/reftek_data; model/reftek/reftek_data => model/reftek_data/reftek_reader
• move common functions between reftek_data and mseed_data from mseed_data to general_data
• Modify code to make new reftek works with others

sohstationviewer/model/general_data/general_data_helper.py

 from typing import List, Dict, Optional, Union, Tuple
 import numpy as np
+import os
+from pathlib import Path
+
 from sohstationviewer.database.extract_data import get_convert_factor
 
 
@@ -207,3 +210,36 @@ def reset_data(selected_key: Union[str, Tuple[str, str]], data_dict: Dict):
                 del selected_data_dict[chan_id][k]
             except KeyError:
                 pass
+
+
+def read_text(path2file: Path) -> Union[bool, str]:
+    """
+    CHANGED FROM handling_data.read_text:
+        + Don't need to check binary because UnicodeDecodeError caught means
+            the file is binary
+
+    Read text file and add to log_data under channel TEXT.
+        + Raise exception if the file isn't a text file
+        + Remove empty lines in content
+    :param path2file: str - absolute path to text file
+    :param file_name: str - name of text file
+    :param text_logs: holder to keep log string, refer to
+        DataTypeModel.__init__.log_data['TEXT']
+    """
+    try:
+        with open(path2file, 'r') as file:
+            content = file.read().strip()
+    except UnicodeDecodeError:
+        return
+
+    if content != '':
+        # skip empty lines
+        no_empty_line_list = [
+            line for line in content.splitlines() if line]
+        no_empty_line_content = os.linesep.join(no_empty_line_list)
+
+        log_text = "\n\n** STATE OF HEALTH: %s\n" % path2file.name
+        log_text += no_empty_line_content
+    else:
+        log_text = ''
+    return log_text