vim/c: added vim setup and c language setup

- added vim setup
- added vim autocomplete guide based on coc
- added c support by coc lsp
- added c setup

wiki/linux/vim/c-language.md

@@ -0,0 +1,39 @@
+# C
+
+C is a common programming language.
+In this entry we will focus on making vim support c and use vim as an ide for c.
+
+## Autocompletion
+
+### Coc
+
+To enable autocompletion for coc you need to install `ccls`.
+After that you need to add the following lines to your coc config file.
+
+```json
+{
+   "languageserver": {
+       "ccls": {
+           "command": "ccls",
+           "filetypes": [
+               "c",
+               "cpp",
+               "objc",
+               "objcpp"
+           ],
+           "rootPatterns": [
+               ".ccls",
+               "compile_commands.json",
+               ".vim/",
+               ".git/",
+               ".hg/"
+           ],
+           "initializationOptions": {
+               "cache": {
+                   "diretory": "/tmp/ccls"
+               }
+           }
+       }
+   }
+}
+```