[Doc] documents update:

(1) install_github is not support due to the usage of submodule

(2) remove part of the markdown which is not displayed correctly, see
https://xgboost.readthedocs.org/en/latest/R-package/discoverYourData.html

R-package/README.md

@@ -19,19 +19,24 @@ We are [on CRAN](https://cran.r-project.org/web/packages/xgboost/index.html) now
 install.packages('xgboost')
 ```
 
-For up-to-date version, please install from github. Windows user will need to install [RTools](http://cran.r-project.org/bin/windows/Rtools/) first.
-
-```r
-devtools::install_git('git://github.com/dmlc/xgboost',subdir='R-package')
-```
-
 You can also install from our weekly updated drat repo:
 ```r
 install.packages("drat", repos="https://cran.rstudio.com")
 drat:::addRepo("dmlc")
 install.packages("xgboost", repos="http://dmlc.ml/drat/", type="source")
 ```
 
+***Important*** Due to the usage of submodule, `install_github` is no longer support to install the
+latest version of R package. 
+For up-to-date version, please install from github. Windows user will need to install [RTools](http://cran.r-project.org/bin/windows/Rtools/) first.
+
+```bash
+git clone --recursive https://github.com/dmlc/xgboost
+cd xgboost
+make Rbuild
+R CMD INSTALL xgboost_0.4-3.tar.gz
+```
+
 For more detailed installation instructions, please see [here](http://xgboost.readthedocs.org/en/latest/build.html#r-package-installation).
 
 Examples

doc/R-package/discoverYourData.md

@@ -1,16 +1,3 @@
----
-title: "Understand your dataset with Xgboost"
-output:
-  rmarkdown::html_vignette:
-    css: vignette.css
-    number_sections: yes
-    toc: yes
-author: Tianqi Chen, Tong He, Michaël Benesty
-vignette: >
-  %\VignetteIndexEntry{Discover your data}
-  %\VignetteEngine{knitr::rmarkdown}
-  \usepackage[utf8]{inputenc}
----
 
 Understand your dataset with XGBoost
 ====================================

doc/R-package/xgboostPresentation.md

@@ -1,17 +1,3 @@
----
-title: "Xgboost presentation"
-output:
-  rmarkdown::html_vignette:
-    css: vignette.css
-    number_sections: yes
-    toc: yes
-bibliography: xgboost.bib
-author: Tianqi Chen, Tong He, Michaël Benesty
-vignette: >
-  %\VignetteIndexEntry{Xgboost presentation}
-  %\VignetteEngine{knitr::rmarkdown}
-  \usepackage[utf8]{inputenc}
----
 
 XGBoost R Tutorial
 ==================

doc/build.md

@@ -180,6 +180,16 @@ First follow [Building on OSX](#building-on-osx) to get the OpenMP enabled compi
   install.packages("xgboost", repos="http://dmlc.ml/drat/", type = "source")
   ```
 
+Due to the usage of submodule, `install_github` is no longer support to install the
+latest version of R package. To install the latest version,
+
+```bash
+git clone --recursive https://github.com/dmlc/xgboost
+cd xgboost
+make Rbuild
+R CMD INSTALL xgboost_0.4-3.tar.gz
+```
+
 ## Trouble Shooting
 
 1. **Compile failed after `git pull`**