Change TextLoader for gap buffer approach

- for CR line endings, convert all CR to LF
- for CRLF line endings, convert all CRLF to LF

src/core/TextLoader.h

@@ -12,29 +12,20 @@ class TextLoader
 {
 public:
     TextLoader();
-    void load_buffer(uint8_t * buffer, size_t size);
+    void load_buffer(uint8_t * buffer, size_t size, size_t * out_size);
     size_t num_lines()
     {
-        if (m_lines == nullptr)
-        {
-            return 0u;
-        }
-        else
-        {
-            return m_lines->size();
-        }
+        return m_num_lines;
     }
     LineEndings::Type get_line_endings() { return m_line_endings; }
     Encoding::Type get_encoding() { return m_encoding; }
-    auto begin() { return m_lines->begin(); }
-    auto end() { return m_lines->end(); }
     bool get_eol_at_eof() { return m_eol_at_eof; }
 
 protected:
     LineEndings::Type m_line_endings;
     Encoding::Type m_encoding;
     bool m_eol_at_eof;
-    std::shared_ptr<std::list<Span>> m_lines;
+    size_t m_num_lines;
 };
 
 #endif