Merged from trunk -r15218:15272

   Merged from trunk -r15218:15272

   | 15220   | Show the path of the lockfile when chown fails. Thanks to    |
   | zmedico | Jeremy Olexa <darkside@g.o> for reporting.                   |

   | 15221   | Enable EAPI 3 and deprecate EAPI 3_pre2.                     |
   | zmedico |                                                              |

   | 15222   | Remove code for svn.IO_error and bzr.IO_error categories     |
   | zmedico | since they don't exist therefore and if this code had ever   |
   |         | executed it would have raised a KeyError.                    |

   | 15272   | Don't ignore CVS/Entries.IO_error when not in commit mode.   |
   | zmedico |                                                              |

svn path=/main/branches/prefix/; revision=15274