fixed assert
extract dialog: generate annotations mnemonic
extract method: use target class context to check nullability
disable param. folding for light extract method object
EDU-299 Incomplete test for lesson 9  task 1
Merge remote-tracking branch 'origin/master'
fix PY-14649 Importing in debug mode fails; works fine in run mode
[git tests] move read all refs to test util
[log] Clarify branch comparison logic & API

Branches layout (and importance) is different from the order of
labels in the commit renderer => use different comparators for this.

For example, HEAD is the most important label and should be displayed
at the first position; but it is the less important branch head
identifier, because we want to keep layout when possible while HEAD
is constantly moving (especially during branch checkout and rebase).
[log] assert access from dispatch thread for remote operation as well
ContainerUtil.toString() for maps which don't implement toString (e.g. THashMap)
[vcs] Throw IAE if not a hash is passed to HashImpl constructor

NumberFormatException is not thrown anymore, since Integer.parseInt()
was changed to Character.digit().
digit() returns -1 instead of throwing an exception which may lead to
incorrect Hash objects if not a hash string is passed. Better to
throw an exception in that case.
[git] Refactor reading branches from repository

More strict separation:
* find branch files;
* read from packed-refs and branch files;
* parse the information to GitBranch objects.

Preparation for IDEA-119168.
[git] IDEA-119168 Support symbolic refs in .git/refs files
[git] ignore tags when reading packed-refs
[git] Simplify reading information from .git

Separate current revision/current branch reading is not used and is
not planned to be used, while reading all the information is fast
enough. Therefore simplify things by reading everything in one pack.

Also don't read from hidden files. IDEA-128461
[git] IDEA-134108 Use correct environment map
[git] When reading .git/packed-refs ignore refs other than refs/heads and refs/remotes
use ArrayList instead of LinkedList
IDEA-130798 (SSR retains too much memory)