Update scaladoc's .classpath to new name of partest project

(see github.com/scala/scala-partest )
review by @dragos
SI-7708 - Improve Bitset foreach performance

1. Switched inner for loop for a while loop to enable early exit when bitset
is sparse.

2. Switched outer for loop for while loop for performance.

3. Changed WordLength and friends to final for performance.

New version runs in 60% of time of old on dense bitsets, faster if highly
sparse.  No tests committed (requires performance testing framework).
SI-7356 - Source.mkString performs painfully slow (...)

1. Wrote a custom mkString for BufferedSource.

2. Moved the logic for rescuing the iterator-buffered char out of
BufferedLineIterator and into a private method in BufferedSource.

Speed test based on the one in the issue tracker (but written correctly)
indicates that performance is equal or better to getLines.  This resolves
SI-7356 in a minimal fashion.
Merge pull request #2929 from Ichoran/issue/7356

SI-7356 - Source.mkString performs painfully slow (...)
Merge pull request #2924 from huitseeker/scala-partest-update

Update scaladoc's .classpath to new name of partest project
Merge pull request #2927 from Ichoran/issue/7708

SI-7708 - Improve Bitset foreach performance
add syntactic extractor for assignment/update trees

Even though updates and assignments look the same syntactically they
are represented differently on the AST level. We need to abstract over
that.