cumulative update of the f14 branch
    
    - do not send QUIT to a dead FTP control connection (#650255)
    - pull back glibc's implementation of str[n]casecmp(), #626470 appears
      fixed
    - prevent FTP client from hanging on unrecognized ABOR response
      (#649347)
    - return more appropriate error code in case FTP server session idle
      timeout has exceeded (#650255)
    - prevent FTP server from hanging on closed data connection (#643656)
    - enforce versioned libssh2 dependency for libcurl (#642796)
    - proxy tunnel support for LDAP requests (#655073)