title: Installation error "no package specified" - trying to install slidify from github in windows
body: <p><strong>When I tried git-hub install, using:</strong></p>
  
  <pre><code>install_github('slidify', 'ramnathv')
  </code></pre>
  
  <p><strong>But I got the follwing message:</strong></p>
  
  <pre><code>&gt; install_github('slidify', 'ramnathv')
  Installing github repo slidify/master from ramnathv
  Downloading master.zip from https://github.com/ramnathv/slidify/archive/master.zip
  Installing package from C:\Users\6E86~1\AppData\Local\Temp\RtmpYD4xRM/master.zip
  Installing slidify
  "C:/PROGRA~1/R/R-31~1.0/bin/i386/R" --vanilla CMD INSTALL "C:\Users\  \
   ע\AppData\Local\Temp\RtmpYD4xRM\devtools1f901f6d4e5e\slidify-master"  \
    --library="C:/Program Files/R/R-3.1.0/library" --install-tests 
  
  Warning: invalid package 'C:\Users\ע\AppData\Local\Temp\RtmpYD4xRM\devtools1f901f6d4e5e\slidify-master'
  Error: ERROR: no packages specified
  Error: Command failed (1)
  </code></pre>
  
  <p><strong>I also tried downlowding "slidify-master.zip" and installing it localy using:</strong></p>
  
  <pre><code> install.packages("c:/r/packages/slidify-master.zip", repos = NULL, type="source")
  </code></pre>
  
  <p><strong>but nothing seems to happen, and the package is not installed:</strong></p>
  
  <pre><code>&gt; library(slidify)
  Error in library(slidify) : there is no package called ‘slidify’
  </code></pre>
  
  <p><strong>my sessionInfo() is:</strong></p>
  
  <pre><code>&gt; sessionInfo()
  R version 3.1.0 (2014-04-10)
  Platform: i386-w64-mingw32/i386 (32-bit)
  
  locale:
  [1] LC_COLLATE=Hebrew_Israel.1255  LC_CTYPE=Hebrew_Israel.1255   
  [3] LC_MONETARY=Hebrew_Israel.1255 LC_NUMERIC=C                  
  [5] LC_TIME=Hebrew_Israel.1255    
  
  attached base packages:
  [1] stats     graphics  grDevices utils     datasets  methods   base     
  
  other attached packages:
  [1] devtools_1.5
  
  loaded via a namespace (and not attached):
  [1] digest_0.6.4   evaluate_0.5.5 httr_0.3       memoise_0.2.1  parallel_3.1.0
  [6] RCurl_1.95-4.1 stringr_0.6.2  tools_3.1.0    whisker_0.3-2 
  </code></pre>
  
  <p><strong>any ideas?</strong></p>