Feature: Config: Normalize link so that user can choose [[]] or []() (Issue #892)

Main change:
        Create function: normalize_syntax_settings(syntax)

Problem:
        Some user prefer [[]] links more than []().
        As vimwiki know both of them, they should be able to choose
        without regex mastery and with tests

Solution:
        let g:vimwiki_syntax_variables.markdown.Link1 = vimwiki#vars#get_global('WikiLinkTemplate1')

autoload/vimwiki/base.vim

@@ -429,11 +429,7 @@ function! vimwiki#base#generate_links(create, ...) abort
     for link in links
       let link_infos = vimwiki#base#resolve_link(link)
       if !vimwiki#base#is_diary_file(link_infos.filename, copy(l:diary_file_paths))
-        if vimwiki#vars#get_wikilocal('syntax') ==# 'markdown'
-          let link_tpl = vimwiki#vars#get_syntaxlocal('Weblink1Template')
-        else
-          let link_tpl = vimwiki#vars#get_global('WikiLinkTemplate1')
-        endif
+        let link_tpl = vimwiki#vars#get_syntaxlocal('Link1')
 
         let link_caption = vimwiki#base#read_caption(link_infos.filename)
         if link_caption ==? '' " default to link if caption not found
@@ -2252,7 +2248,7 @@ endfunction
 
 
 " Treat link string towards normalization
-" [__LinkDescription__](__LinkUrl__.FileExtension)
+" [__LinkDescription__](__LinkUrl__.__FileExtension__)
 function! vimwiki#base#normalize_link_helper(str, rxUrl, rxDesc, template) abort
   let url = matchstr(a:str, a:rxUrl)
   if vimwiki#vars#get_wikilocal('syntax') ==# 'markdown' && vimwiki#vars#get_wikilocal('markdown_link_ext')
@@ -2284,6 +2280,7 @@ endfunction
 
 
 " Normalize link in a diary file
+" Refactor: in diary
 function! vimwiki#base#normalize_link_in_diary(lnk) abort
   let sc = vimwiki#vars#get_wikilocal('links_space_char')
   let link = a:lnk . vimwiki#vars#get_wikilocal('ext')
@@ -2313,7 +2310,7 @@ function! vimwiki#base#normalize_link_in_diary(lnk) abort
   endif
 
   if vimwiki#vars#get_wikilocal('syntax') ==? 'markdown'
-    let template = vimwiki#vars#get_syntaxlocal('Weblink1Template')
+    let template = vimwiki#vars#get_syntaxlocal('Link1')
   endif
 
   return vimwiki#base#normalize_link_helper(str, rxUrl, rxDesc, template)
@@ -2380,13 +2377,8 @@ function! s:normalize_link_syntax_v() abort
   if vimwiki#base#is_diary_file(expand('%:p'))
     let link = vimwiki#base#normalize_link_in_diary(visual_selection)
   else
-    " Warning nested syntax discrimination
-    if vimwiki#vars#get_wikilocal('syntax') ==# 'markdown'
-      let template = vimwiki#vars#get_syntaxlocal('Weblink1Template')
-    else
-      let template = vimwiki#vars#get_global('WikiLinkTemplate1')
-    endif
-    let link = s:safesubstitute(template, '__LinkUrl__', visual_selection, '')
+    let link_tpl = vimwiki#vars#get_syntaxlocal('Link1')
+    let link = s:safesubstitute(link_tpl, '__LinkUrl__', visual_selection, '')
   endif
 
   " Transform link:

autoload/vimwiki/markdown_base.vim

@@ -102,7 +102,7 @@ function! s:normalize_link_syntax_n() abort
     else
       let sub = vimwiki#base#normalize_link_helper(lnk,
             \ vimwiki#vars#get_global('rxWord'), '',
-            \ vimwiki#vars#get_syntaxlocal('Weblink1Template'))
+            \ vimwiki#vars#get_syntaxlocal('Link1'))
     endif
     call vimwiki#base#replacestr_at_cursor('\V'.lnk, sub)
     return

autoload/vimwiki/tags.vim

@@ -360,7 +360,7 @@ function! vimwiki#tags#generate_tags(create, ...) abort
             let link_tpl = vimwiki#vars#get_syntaxlocal('Weblink3Template')
             let link_infos = vimwiki#base#resolve_link(taglink)
             if empty(link_infos.anchor)
-              let link_tpl = vimwiki#vars#get_syntaxlocal('Weblink1Template')
+              let link_tpl = vimwiki#vars#get_syntaxlocal('Link1')
               let entry = s:safesubstitute(link_tpl, '__LinkUrl__', taglink, '')
               let entry = s:safesubstitute(entry, '__LinkDescription__', taglink, '')
             else

autoload/vimwiki/vars.vim

@@ -563,7 +563,7 @@ endfunction
 
 
 " Helper path
-" TODO move to path
+" TODO move to path: Conflict with: vimwiki#path#path_norm && vimwiki#path#normalize
 function! s:normalize_path(path) abort
   " trim trailing / and \ because otherwise resolve() doesn't work quite right
   let path = substitute(a:path, '[/\\]\+$', '', '')
@@ -741,6 +741,8 @@ function! vimwiki#vars#populate_syntax_vars(syntax) abort
   if a:syntax ==# 'markdown'
     call s:populate_extra_markdown_vars()
   endif
+
+  call s:normalize_syntax_settings(a:syntax)
 endfunction
 
 
@@ -975,6 +977,23 @@ function! s:populate_extra_markdown_vars() abort
 endfunction
 
 
+" Normalize syntax setting
+"   so that we dont have to branch for the syntax at each operation
+" Called: vimwiki#vars#populate_syntax_vars
+function! s:normalize_syntax_settings(syntax) abort
+  let syntax_dic = g:vimwiki_syntax_variables[a:syntax]
+
+  " Link1: used when:
+  "   user press enter on a non-link (normalize_link)
+  "   command generate link form file name (generate_link)
+  if a:syntax ==# 'markdown'
+    let syntax_dic.Link1 = syntax_dic.Weblink1Template
+  else
+    let syntax_dic.Link1 = vimwiki#vars#get_global('WikiLinkTemplate1')
+  endif
+endfunction
+
+
 " ----------------------------------------------------------
 " 4. Getter, Setter (exported)
 " ----------------------------------------------------------