bundle install fail "..does not appear to be a git repository fatal: Could not read from remote repository."

I have a gem file in which i am trying to get "gem 'twitter-bootstrap-rails', git: 'http://ift.tt/1CSqjcL'"

using bundle install command and it gives the below error

C:\Sooraj\Playdrone\playdrone-master>bundle install

Fetching http://ift.tt/1CSqjcL fatal: '/cygdrive/c/Sooraj/Playdrone/playdrone-master/C:/Ruby22/lib/ruby/gems/2. 2.0/cache/bundler/git/twitter-bootstrap-rails-eff46a5fc3c9c652c290119047c5ec9247 068903' does not appear to be a git repository fatal: Could not read from remote repository.

Please make sure you have the correct access rights and the repository exists. Retrying git clone --no-checkout --quiet "C:/Ruby22/lib/ruby/gems/2.2.0/cache/bu ndler/git/twitter-bootstrap-rails-eff46a5fc3c9c652c290119047c5ec9247068903" "C:/ Ruby22/lib/ruby/gems/2.2.0/bundler/gems/twitter-bootstrap-rails-38476dbd7f9a" du e to error (2/4): Bundler::Source::Git::GitCommandError Git error: command git clone --no-checkout --quiet "C:/Ruby22/lib/ruby/gems/2.2.0/cache/bundler/git/twi tter-bootstrap-rails-eff46a5fc3c9c652c290119047c5ec9247068903" "C:/Ruby22/lib/ru by/gems/2.2.0/bundler/gems/twitter-bootstrap-rails-38476dbd7f9a" in directory C :/Sooraj/Playdrone/playdrone-master has failed. If this error persists you could try removing the cache directory 'C:/Ruby22/lib /ruby/gems/2.2.0/cache/bundler/git/twitter-bootstrap-rails-eff46a5fc3c9c652c2901 19047c5ec9247068903' fatal: '/cygdrive/c/Sooraj/Playdrone/playdrone-master/C:/Ruby22/lib/ruby/gems/2. 2.0/cache/bundler/git/twitter-bootstrap-rails-eff46a5fc3c9c652c290119047c5ec9247 068903' does not appear to be a git repository fatal: Could not read from remote repository.

but the git url is correct.Its asking me to delete the cache folder and i delete it and run the commmand and i get the same error.

can anyone please help what this error is and how i can rectify?? Thanks a lot