feat: added modifier to have solid inner borders in UTF-8 tables

CHANGELOG.md

@@ -7,6 +7,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 ### Added
 
+- Add `modifiers::UTF8_SOLID_INNER_BORDERS`, which makes the inner borders solid lines: `│─` by [ModProg](https://github.com/ModProg) for [#39](https://github.com/Nukesor/comfy-table/issues/39).
 
 ## [4.0.1] - 2021-07-08
 

src/style/modifiers.rs

@@ -9,3 +9,15 @@
 /// ╰───────┴───────╯
 /// ```
 pub const UTF8_ROUND_CORNERS: &str = "               ╭╮╰╯";
+
+/// A modifier, that when applied will convert the inner borders to solid lines.
+/// ```text
+/// ╭───────┬───────╮
+/// │ Hello │ there │
+/// ╞═══════╪═══════╡
+/// │ a     │ b     │
+/// ├───────┼───────┤
+/// │ c     │ d     │
+/// ╰───────┴───────╯
+/// ```
+pub const UTF8_SOLID_INNER_BORDERS: &str = "        │─         ";