svn: Refactored SvnConfiguration - code simplified, fields renamed

(cherry picked from commit 0839212de01f016e4df5762ba56eda5c030dc5d9)
svn: Implemented ability to configure ssh tunnel for svn command line client in Subversion Settings

(cherry picked from commit e63be33c0b18bc1a0de4be7dc1474b85a0df7d0b)
IDEA-130923 Run ContentRevisionCache.clearScope() logic under read action

Previous ContentRevisionCache.clearScope() logic performed custom lock and then implicitly run read actions during calls to VcsDirtyScope.belongsTo() - so deadlock could occur when ContentRevisionCache.clearScope() (or other method that also requires corresponding custom lock) is called simultaneously from other thread under write action.
To prevent such cases all ContentRevisionCache.clearScope() logic is wrapped with read action.

(cherry picked from commit c1244e38e50bd69a45fa71489c428d34753cecc9)
svn: Refactored ForNestedRootChecker - code simplified, @NotNull, inlined "goIntoNested" parameter of getAllNestedWorkingCopies() (as its value is false for all code paths)

(cherry picked from commit aa844045de4a48eec6efcbba9e1736f962db543e)
IDEA-130628 Only check directories (and not both files and directories) while detecting svn working copies for project

(cherry picked from commit de4c0abafbc19114378769496533352e692b0810)
IDEA-130628 Optimized svn working copies detection logic - only run "svn info" command on directory if it is either root directory (the one where detection was started) or has ".svn" child directory

(cherry picked from commit ad4434a2c18de7d87590f9a331b606dd8634de00)
Merge remote-tracking branch 'origin/139' into 139