Text Editor: Add GLSL support language

Pr adds the Glsl language to the text editor.
The objective is to be able to create your own GLSL shaders in blender. This improves the workflow since all shader programming can be done directly in Blender. In addition, the GLSL language is a very popular language in the video games industry and even in general.
The goal is then to also support HSLS in the same way in order to have a complete solution with OSL, GLSL and HLSL
If there are any key words or other missing words, tell me

@@ -0,0 +49,4 @@
+    "mat4"
+    "out"
+    "return"
+    "sampler1D"

@@ -0,0 +24,4 @@
+
+static int textformat_glsl_literals_builtinfunc_data[]
+{
+    "Array"

@@ -0,0 +115,4 @@
+    "volatile"
+    "while"
+    "#define"
+    "#defined"

@@ -0,0 +167,4 @@
+    "dFdy"
+    "distance" 
+    "dot"
+    "dxdx"

@@ -0,0 +192,4 @@
+    "greaterThan"
+    "greaterThanEqual"
+    "groupMemoryBarrier"
+    "idexp"

@@ -0,0 +390,4 @@
+
+
+    if       (txtfmt_glsl_find_specialvar(str)   != -1) {fmt = FMT_TYPE_SPECIAL;}
+     else if (txtfmt_glsl_find_builtfunc(str)    != -1) {fmt = FMT_TYPE_KEYWORD;}

@@ -0,0 +19,4 @@
+
+#include "text_format.hh"
+
+/*---------------------------------------------------------------------*/

@@ -0,0 +288,4 @@
+  /*Add in futur verion when GLSL 4.5 support in Blender*/
+  /*"textureSamples"*/
+
+  /*Built-In Variable */

@@ -0,0 +548,4 @@
+    str++;
+  }
+
+  /* Terminate and add continuation char */

@@ -0,0 +10,4 @@
+/*"include <cstring> can be replace by import std:string;"*/
+
+
+#include "BLI_blendlib.h"

@@ -0,0 +23,4 @@
+/* Define all keywords who can use
+*/
+
+static int textformat_glsl_literals_builtinfunc_data[] = {

@@ -0,0 +392,4 @@
+   } else if (txtfmt_glsl_find_builtfunc(str)    != -1) {fmt = FMT_TYPE_KEYWORD;
+   } else if (txtfmt_glsl_find_reserved(str)     != -1) {fmt = FMT_TYPE_RESERVED;
+   } else if (txtfmt_glsl_find_preprocessor(str) != -1) {fmt = FMT_TYPE_DIRECTIVE;
+   } else                                               {fmt = FMT_TYPE_DEFAULT;

@@ -0,0 +406,4 @@
+    FlattenString fs;
+    const char *str;
+    char *fmt;
+    char cont_orig, cont, find, prev = '';

@@ -0,0 +526,4 @@
+        /* keep in sync with `txtfmt_glsl_format_identifier()`. */
+
+        if       ((i = txtfmt_glsl_find_specialvar(str))   != -1) {prev = FMT_TYPE_SPECIAL;
+        }else if ((i = txtfmt_glsl_find_builtinfunc(str))  != -1) {prev = FMT_TYPE_KEYWORD;

@@ -0,0 +241,4 @@
+    "texelFetchOffset"
+    "texture"
+    "texture1D"
+    "texture1DLod"